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NOAA Estuary-of-the-Month 
Seminar Series No. 13 

f \ 32 (e 

/ FEB 1 3 1989 j 

Galveston Bay: 

Issues, Resources, 

Status, and Management 


February 1989 



U.S. DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric Administration 

NOAA Estuarine Programs Office 














/ 

NOAA Estuary-of-the-Month 
Seminar Series No. 13 



Galveston Bay: 

Issues, Resources, 

Status, and Management 


Proceedings of a Seminar 
Held March 14, 1988 
Washington, D.C. 


U.S. DEPARTMENT OF COMMERCE 

C. William Verity, Secretary 

National Oceanic and Atmospheric Administration 

William E. Evans, Under Secretary 

NOAA Estuarine Programs Office 

Virginia K. Tippie, Director 


~Th ni 

^HG 3* 

\W 


ft*}- £t> A o <y 






57*7 2 ^ s c £°i 


The NO A A Estuarine Programs Office 
and 

The U.S. Environmental Protection Agency 
present 


An Estuary-of-the-Month Seminar 

Galveston Bay 

Issues, Resources, Status, and Management 


March 14,1988 


U.S. Department of Commerce 
14th and Constitution Avenue, N.W. 
Room 4830 
Washington, D.C. 


iii 


Acknowledgement 


We gratefully acknowledge the assistance of Drs. Terry Whitledge of The University of Texas 
Marine Science Institute and Sammy Ray of Texas A&M University at Galveston, who had principal 
responsibility for assembling the speakers and whose familiarity with the bay area and its people 
were invaluable. The seminar was coordinated in Washington, D.C.,by Catherine L. Mills, Estuarine 
Programs Office Regional Coordinator, with the help of other members of the EPO staff. We would 
also like to express our appreciation to the administrators and information staff of the Texas A&M 
University Sea Grant College Program, who produced both the Executive Summary and this final 
document. 


T AMU-SG-88-115 
A/I-l 

NA85AA-D-SG128 

Questions concerning these proceedings may be directed to the NOAA Estuarine Programs 
Office by writing to Room 625 Universal South, 1825 Connecticut Avenue, N.W., Washington, D.C. 
20235, or by calling (202) 673-5243. 


iv 


Foreword 


The following are the proceedings of a seminar on Galveston Bay, held on March 14,1988, at the 
Herbert C. Hoover Building of the U.S. Department of Commerce in Washington, D.C. The Estuarine 
Programs Office (EPO) of the National Oceanic and Atmospheric Administration (NOAA) spon¬ 
sored this seminar as a part of the continuing series of "Estuary-of-the-Month" Seminars, held with 
the objective of bringing to public attention important research and management issues of our 
nation's estuaries. To this end, participants first presented historical and scientific overviews of the 
bay area, followed by an examination of management issues by scientists and research managers 
involved in Galveston Bay. 
























Contents 


Preface.ix 

Introduction.1 

Geology, Climate and Water Circulation of the Galveston Bay System.3 

Biological Components of Galveston Bay.23 

Galveston Bay and the Surrounding Area: Human Uses, Production 

and Economic Values.53 

Issue and Information Needs.67 

Management Issues: Galveston Bay.79 

Summary.89 

Keynote Address, The Honorable Lloyd Bentsen .95 

Appendix I—Selected Figures.97 


Oil and Gas Development 

Seismic Exploration Activity 

Federal Navigation Channels and Disposal Areas 

Sensitive Cultural Resources 

Sensitive Biological Resources 

Oyster Fisheries Resources of Galveston Bay 

Galveston Bay System Watershed 

Fresh Water Flows and Point Source Discharges 

Appendix II—Steering Committee and Resource Personnel.107 


vii 













Galveston Bay 



viii 


Photo— Norman Martin, Texas Sea Grant Program 




Preface 


The Galveston Bay estuary is the second largest coastal embayment in the State of Texas and is 
surrounded by a population of nearly three million people in the Houston region. Galveston Bay has 
served the State of Texas by producing avenues for navigation, cooling water for industries, 
receptacle for discharges, playground for outdoor recreation and a pantry for seafood. All of these 
often conflicting uses have taken Galveston Bay close to the environmental precipice of degradation. 
Only with careful and prudent management can Galveston Bay be as "all-serving" in the future as 
it has in the past. It was this task of preserving the ecological balances in Galveston Bay that coalesced 
this group of concerned scientists and managers to present a holistic overview of what is known 
about the health of Galveston Bay, detail the multiple use conflicts and present a summary of research 
needs that would be useful for management. There is not enough room in the introduction to list all 
of the contributing organizations that provided the time and resources of their personnel to produce 
the Galveston Bay Seminar and the written texts (Appendix II). However, as organizers we would 
like to thank all of the participants for their contributions and congratulate them for a job well done. 
It was a pleasure interacting with university, local, state and federal agencies in striving for a common 
goal to preserve Galveston Bay. 


Terry E. Whitledge 
Sammy M. Ray 
Co-Organizers, 
Galveston Bay Seminar 


IX 





Introduction 

Sammy M. Ray and A.R. (Babe) Schwartz 


In May 1987 the National Oceanic and Atmospheric Administration's Estuarine Programs Office 
invited Terry Whitledge and Sammy Ray to organize a seminar on Galveston Bay for presentation 
in the "Estuary-of-the-Month" seminar series. We immediately convened a meeting of about 30 
individuals, representing federal, state, universities and private organizations to develop this 
seminar. Since May 1987 we have held several meetings involving representation from user groups 
and regulatory agencies to develop an objective presentation of the uses, values, conflicts and 
problems of one of the nation's most important estuarine systems. After several months of hard work 
by many individuals, we are pleased to have the opportunity to tell the "Galveston Bay" story in our 
nation's capital. 

Although Texas does not have a formal Coastal Zone Management Program, the state has 
expended $5 million in a five-year effort to develop such a plan. This effort, while directly 
unsuccessful, has resulted in the enactment of several legislative measures relating to coastal 
environmental affairs, which began with the passage of the Open Beaches Act of 1958. With this 
landmark beginning, other major coastal environmental acts followed in rapid succession. These acts 
included the following: 

• Texas Sea Grant Program —1968 

• Gulf Coast Waste Disposal Authority —1969 

• Texas Coastal and Marine Council — 1971 

• Public Right to Freshwater Inflow — 1971 

• Coastal Public Lands Management Act —1973 

• Texas Energy and Natural Resources Council — 1978 

Each of these legislative actions, as well as other related acts, leaves no doubt that Texas has been 
more active in protecting its coastal environment than the lack of a formal Coastal Zone Management 
Program indicates. The passage of the Coastal Public Lands Management Act of 1973 is noteworthy 
in that, for the first time, it provided a mechanism for the comprehensive management of all state- 
owned submerged lands (1.75 million acres) in the bays and estuaries of Texas. As a part of the public 
lands management program, a submerged lands inventory depicting wetlands, oyster reefs, rooker¬ 
ies, sediment types, habitat assemblages, petroleum wells and pipelines, etc., has been developed. 
Furthermore, all submerged lands of Texas (4.2 million acres) have been "coded" environmentally 
by federal and state regulatory agencies to identify and locate environmentally sensitive habitats 
such as wetlands, submerged grass beds, rookeries and habitats for endangered species, etc. (See 
selected figures in Appendix I.) 

Another important step was taken by the Honorable William P. Clements, Jr., Governor of Texas, 
in his letter of May 29, 1987, to Mr. Lee M. Thomas, Administrator of the U.S. Environmental 
Protection Agency, nominating Galveston Bay as an estuary of national significance to be preserved 
for the use and enjoyment of future generations. 

Shortly following Governor Clements' action, several environmentally concerned individuals 
organized the Galveston Bay Foundation. The development of this foundation, with trustees and 
members from all walks of life, is a monumental step toward ensuring a public advocate for the 
preservation of one of our most valuable national resources — Galveston Bay. Moreover, we believe 
that the Galveston Bay Foundation will provide the grass roots impetus for the establishment of a 
statutory Coastal Zone Management Program for Texas. 


1 






































































































Geology, Climate and Water 
Circulation of the Galveston Bay 

System 

E.G. Wermund, Robert A. Morton, Gary Powell 1 


Abstract 

E.G. WERMUND—The geology of the Galveston Bay System reflects its location in one of the 
world's largest depositional basins, the northwest Gulf Coast Basin, as well as changes in the rates 
and balance among sea level, sediment influx and basin subsidence. Sedimentary deposits of two 
ages dominate the surficial geology surrounding the bays. Deposits of the most recent interglacial 
period of the Pleistocene Epoch include (1) river sands and floodbasin muds of a deltaic plain and 
(2) sands of a barrier island system. Modem (Holocene) sediments that entrench and overlie the older 
strata are (1) fine sand and mud in rivers and bayhead deltas; (2) mud in the bays; (3) oyster reefs in 
the bays; and (4) sand composing the youngest barrier islands. Galveston Bay is extremely shallow 
(10 to 12 feet deep) compared with its large areal extent of 600 square miles. Sediment samples, 
collected a mile apart, are mud in most of the bays; samples coarsen shoreward where sand and 
reworked shell (gravel) dominate. Geochemical analyses of sediment samples indicate that abnor¬ 
mally high concentrations of barium, boron, chromium, copper, lead, nickel and zinc are products 
of anthropogenic activities and pollutants. 

The Galveston Bay System has a subhumid, subtropical climate; mean summer high temper¬ 
atures are in the upper 80s (T), and mean winter low temperatures are in the mid 40s ( # F). Mean 
annual rainfall and surface-water evaporation are approximately 50 inches. Summer winds are 
dominantly moderate and southerly; winter brings frequent aperiodic strong north winds. Droughts 
and hurricanes are frequent. Bay circulation is controlled by balances among freshwater influx, tides 
and storm winds. The Trinity and San Jacinto River Basins provide more than 88 percent of the 
freshwater inflow to the bays. Bay tides are diurnal in a 14-day cycle, and maximum tidal range is 
about 2 feet. Hurricane landings may raise the bay level to 15 feet, whereas strong north winds may 
locally lower bay level about 2 feet. 

Principal geologic processes currently altering the Galveston Bay System include (1) a relative sea 
level rise (about 2 feet in this century) and subsidence (nearly 10 feet at Johnson Space Center) in 
response to withdrawal of subsurface water, oil and gas; (2) active faulting; and (3) coastal erosion 
and deposition. Between 1850 and 1982 bay shorelines eroded at an average rate of 2.2 feet per year; 
before 1930 the erosion rate was 1.8 feet per year, whereas the post-1930 rate was 2.4 feet per year. 

Human activities commonly overprint normal natural processes and effect a loss of natural 
resources. Models of circulation, salinity and nutrients developed by the Texas Water Development 
Board indicate potential management problems. Further documentation and regular, selective 


’E.G. Wermund and R.A. Morton represent the Bureau of Economic Geology, The University of Texas at 
Austin; Gary Powell, the Texas Water Development Board. 

This paper is published by permission of the Director, Bureau of Economic Geology. 


3 



process monitoring are needed for future holistic management of the Galveston Bay System to be 
successful. 


Introduction 

The State-owned submerged lands of Texas include about 1.4 million acres of the inner contin¬ 
ental shelf extending about 10.3 miles offshore in the Gulf of Mexico and 1.5 million acres of bays, 
estuaries and lagoons. Peripheral to these inland bay waters are about 1.1 million acres of marshes 
and other wetlands. 

The Galveston Bay System is one of seven major bays and estuaries along the Texas coast. It 
contains four major related bays (Figure 1.1); the center of the system is located at approximately 
29 30' N and 94 42' W. The two principal water bodies are Galveston Bay at the outflow of the San 
Jacinto River and Trinity Bay at the outflow of the Trinity River. Buffalo Bayou, a tributary of the San 
Jacinto River, and Clear Creek have moderate-sized drainage basins contributing freshwater inflow 
to Galveston Bay. East Bay lies landward of Bolivar Peninsula and receives minor freshwater inflows 
from the drainage of Oyster Bayou, a small stream. West Bay is located landward of Galveston Island, 
a barrier island, and receives minor inflow from Chocolate Bayou. Southwest and landward of Follets 
Island are Bastrop and Christmas Bays, which are comparatively small and essentially isolated from 
all water sources except tidal exchange. The Intracoastal Waterway enters East Bay at its easternmost 
location, traverses the southern limits of the bay system behind the barriers, and exits the system 
through the westernmost shore of Christmas Bay. 

Only two tidal inlets permit significant tidal circulation between the brackish water of the bay 
system and the marine water of the Gulf of Mexico. Bolivar Roads is the major inlet through which 
international ships travel to the Port of Houston. San Luis Pass is a minor but important inlet for tidal 
exchange, and both commercial and sport fishing boats use the inlet daily. Rollover Pass, a manmade 
cut through Bolivar Peninsula, provides minor tidal circulation at the eastern end of East Bay. 

The Galveston Bay System is large, encompassing about 340,000 acres (600 square miles) of areal 
extent, and has a simple geometry. Except for spoil banks and oyster reefs, the bay floor is generally 
flat and regular. It is very shallow, having a maximum depth of about 12 feet (Figure 1); Trinity Bay 
is mostly less than 10 feet deep. East Bay is less than 8 feet deep, and West Bay is less than 6 feet deep. 
Extreme vertical exaggeration of a bay profile is necessary to illustrate bay geometry and changes in 
elevation. Gulf Coast bays are all very shallow compared with most bays in the United States. 

The terrain about the Galveston Bay System has subdued topography and low relief. The coastal 
plain slopes gently gulfward less than 1 foot per mile, forming a gentle incline at the land-water 
contact. Bay shorelines may be marshes or small beaches composed solely of shell, sand or mud, or 
more commonly a combination of these sediments. Because of the small gradient of the coastal lands, 
a sea-level rise of a few feet can flood the coastal zone inland for many miles. Along some segments 
of the bay shore, wave-cut bluffs more than 8 feet high occur locally. 

Geology 

The geology of the Galveston Bay System and environs strongly reflects a dynamic geologic 
province. Dynamic in this sense does not mean active seismically (subject to earthquakes) but does 
denote slow, continuous processes reflecting sedimentation, subsidence, faulting and erosion, as 
well as catastrophic changes caused by hurricanes. 

Geologic Framework 

The Galveston Bay System is a small part of the northern Gulf Coast Basin, a large area of 
sedimentary deposition lying between Mexico and Florida. The basic structural and stratigraphic 
framework of the basin was established in the late Triassic and Jurassic (1), when the North American 
plate separated from the African and South American plates. During early rifting, the principal 
deposits were Triassic red beds. Soon after, the basin became isolated, and water inflow was 
restricted, resulting in the deposition of thick evaporite sections dominated by salt. A major salt basin 
underlies the Houston Embayment and is the source of local salt domes that produce salt, sulfur, and 
oil and gas. 


4 



Figure 1.1. Index map of Galveston Bay System locations. Shown are the bays, inlets and streams flowing into the 
system. The profile illustrating the geometry of the bay bottom has a vertical exaggeration of 132x. 


5 


EO 































































































Figure 1.2. Representative cross-section depicting the style of deposition and deep geologic structure in theGalveston Bay 
system area , modified from Morton and others (1985). 


6 






























































































Since salt deposition, the basin has filled principally by prograding sands and muds and, to a 
lesser degree, by transgressive carbonates. The Triassic to modem sediments vary from less than 3 
feet to as much as 50,000 feet in thickness (2). Fluvial and upper deltaic plain sands and muds 
compose the thinner onshore (updip) part of the sedimentary sequence; deltaic sands and muds and 
organic-rich slope muds with fine sands and silts form the thickest part of the section. Distal-slope 
and abyssal muds rapidly thin in the far offshore part of the basin fill. 

Overlying the salt, Jurassic and lower Cretaceous continental sediments filled the salt withdrawal 
basins. Superimposed Cretaceous deposits are dominated by shelf-edge carbonate systems of reefal 
and bank origins that commonly grade into calcareous, organic, very fine grained slope sediments. 
Cenozoic facies are dominated by overlapping, progradational sediments similar to those now being 
deposited by the Mississippi River on its delta and adjacent shelf and slope. The combination of salt 
gliding under loading, salt diapirism, salt withdrawal from basins and associated faulting, and low- 
angle, down-to-the-coast growth faulting characterizes the deep geologic structure of the north¬ 
western Gulf Coast Basin. Figure 2 is a representative cross section illustrating the stratigraphy and 
structure near the study area (3). 

The Gulf Coast Basin is a rich petroleum province, and numerous oil and gas fields produce from 
traps underlying the Galveston Bay System and adjacent onshore properties. A major oil and gas 
play, the deep-seated Frio salt dome play (4), occurs in an area of deeply buried salt diapirs sur¬ 
rounded by shallow piercement domes that formed contemporaneously with the Frio-age (Oligo- 
cene) Houston delta system. Cedar Point and Trinity oil fields underlie the bay and have produced, 
respectively, 13.2 and 21.2 million barrels of oil. On the west side of Galveston Bay, Clear Lake (22.1 
mmbbl), Gillock (24.4 mmbbl). South Gillock (20.7 mmbbl). East Gillock (44.3 mmbbl), and Webster 
(528.0 mmbbl) are onshore fields producing from the same play. In addition, many other productive 
fields occur in smaller plays containing sandstone reservoirs formed in progradational sequences, 
faulted zones and deformed strata surrounding salt diapirs. 

Surficial Geology 

The surficial deposits surrounding the Galveston Bay System represent only recent geologic 
history, the final depositional and erosional phases of the Pleistocene ice ages, and the Holocene post¬ 
glacial events (5) (Figure 3). The major control effecting most geomorphic features and sedimentary 
deposits is the recent history of sea-level fluctuations. Sea level was lowered by nearly 450 feet when 
glaciers advanced to their farthest limits on the northern continents. Then streams like the San Jacinto 
and Trinity Rivers eroded deep broad valleys entrenched into the land and former continental 
shelves and deposited their sedimentary loads onto the former shelf and slope. Sea level was highest 
when the glaciers melted and retreated. A rising sea inundated the entrenched valleys, and the locus 
where the streams deposited their sediments progressively shifted landward. All the modem sed¬ 
imentary systems owe their attributes to the most recent sea-level rise following the last major glacial 
advance in North America. The size and shape of bays, inlets and barrier islands reflects this most 
recent eustatic cycle. 

Two Pleistocene formations, the Beaumont and Deweyville Formations, crop out near Galveston 
Bay. The Beaumont Formation is composed predominantly of clay, silt and sand where the sediments 
were deposited in fluvial, delta plain and bay environments. A large river system, having meander 
channels larger than those of today, transported mainly sand and silt when sea level was lowered 
during glaciation and while sea level rose during interglacial periods. An extensive Beaumont deltaic 
plain is composed of sand and silt deposited in the distributary channels and of organic-rich clays 
and silts deposited in the interdistributary areas. Locally, fine-grained and fossiliferous muds 
represent former bay deposits. Some Beaumont sediments are composed of mostly fine-grained sand 
arranged in linear trends parallel to the coast. These linear features are higher in elevation (>8 feet) 
than surrounding sediments, and they are characterized by pimple mounds and circular depres¬ 
sions. These sand-rich deposits represent a former barrier island much like those of the modem Gulf 
Coast. 

The Deweyville Formation, which is generally younger than the Beaumont Formation, contains 
coarser grained sediments including gravel. These fluvial-dominated sandy sediments rarely con¬ 
tain clay and silt except in outcrops of backswamp facies. Deweyville exposures, which also exhibit 


7 





Figure 13. Simplified map of Pleistocene and Holocene depositional system of the Galverston area, after Fisher and others, 
1972 (5). 



Figure 1 A. Cross-section of Galveston Island showing the grain-size distribution,accretionary ridges and bedding planes 
(dotted lines), after Bernard and others, 1970 (6). 


8 


e o 


























































meander scars that are larger than those of modem rivers, crop out in terraces above the Trinity and 
San Jacinto floodplains. Although the Pleistocene streams appear to have been larger, the geologic 
processes forming Beaumont and Deweyville deposits resemble those active today in the vicinity of 
the Galveston Bay System. 

The Holocene units on the geologic map (5) are like the Pleistocene deposits described above, 
except for one anthropogenic unit, fill and spoil. These man-made deposits, readily seen at a scale of 
1:250,000, occur along Buffalo Bayou and the Houston Ship Channel, formerly in the San Jacinto River 
floodplain, in the Texas City Dike, in much of Pelican Island, and behind the northeast end of Gal¬ 
veston Island. Very fine sand, silt and clay compose the Quaternary alluvium in the valleys of the 
Trinity and San Jacinto Rivers and the bayhead deltas where the rivers empty into the bays. Slightly 
finer sediments dominate minor stream valleys, because these streams derive their load from the 
surrounding Pleistocene sediments. Fine sands containing some shell are the principal sediments 
composing two modem barrier islands, Galveston Island and Bolivar Peninsula. 

Aerial photographs, cores and radiocarbon dates permit reconstruction of the geologic history of 
Galveston Island (6). Linear ridges and swales nearly parallel to the present shoreline are clear 
evidence of the seaward accretion. The barrier is composed of fine sand at the surface, which becomes 
finer both deeper and seaward, and beds dipping seaward slope increasingly less at depth (Figure 
4). Maximum thickness of the well-sorted, relatively pure barrier sand is about 30 feet. The basal 
strata are approximately 5,300 years old. Galveston Island formed a narrow sand bar and enlarged 
with the seaward accretion of offlapping fine sand (Figure 4). Because of the thickness of the deposit, 
the attitude of the bedding and bulwarking of underlying stiff Pleistocene clays, a relatively stable 
barrier island results, in contrast to the less stable barriers of the east coast of the United States. 

Bay Geology 

Researchers at the Texas Bureau of Economic Geology (7) described the geology of the bay floor 
using samples collected on 1-mile centers in the bays and about 1 mile apart in tidally affected 
streams. Sampled sediments came from a thin veneer overlying the coarser Pleistocene/Holocene 
sediments that filled entrenched valleys during the sea-level rise. Samples were classified on the basis 
of relative percentages of gravel (shell and rare rock fragments), sand and mud (silt and clay). Mud 
composes the largest expanses of the bay, especially in the deep bay centers (Figure 5). Gravel (shell) 
is more common in very shallow water and adjacent to shorelines. Gravel (shell) and sand occur only 
in the highest energy environments; both are more abundant near the shorelines and in shallow water 
affected by storm waves. Oyster reefs form the only other sediment type in the bays. Because of their 
high calcium content, they are comparable to limestones in older rocks. 

In addition to measuring the textural characteristics of the bay sediments, researchers conducted 
multi-element chemical analyses on most samples (Table 1). Total organic carbon was measured 
separately. Thirty major and trace elements were analyzed spectrographically, of which 11 elements 
were reported. These selected metals—barium, boron, calcium, chromium, copper, iron, lead, man¬ 
ganese, nickel, strontium and zinc—are useful for understanding the geology of the bay and for 
detecting anthropogenic impacts on the bay. Largest boron concentrations (+148 ppm) occur in bay 
muds having the highest total organic carbon. Manganese also associates with greater organic carbon 
concentrations in fine-grained sediments (400-1,800 ppm). Highest strontium concentrations (>1,000 
ppm) are in oyster reefs. Because metals are frequently associated with industrial pollution, those are 
reported separately in Table 1 with natural levels versus contaminated sediment values. 

Bay sediments have probably been affected by salt diapirism and/or faulting, but satisfactory 
data are unavailable; thus, the effects of these processes on bay geology cannot be assessed. 

Climate 

The Galveston Bay System lies within the warm part of the temperate zone of the Northern 
Hemisphere. Texas climate is controlled by (1) latitude, (2) proximity to the Gulf of Mexico, (3) winds 
blowing gulfward from Pacific and Arctic frontal systems, (4) decreasing elevation north and west 
to south in Texas, and (5) a position west of the Bermuda high-pressure cell (8). The Galveston area 
has a modified maritime climate controlled by the Gulf of Mexico and is classified as subtropical- 
subhumid. 


9 



CLASSIFICATION OF SEDIMENTS 


OA 9691 


Figure 15. Geologic map of Galveston Bay sediments, after McGowen and Morton, 1979 (7), and White and others, 1985 
(7). 


10 



























Table 1.1. Comparison of Trace Element Concentrations in Sediments (Mud) of the Galveston-Houston Area with Those in Uncontami¬ 
nated Sediments (Baseline Levels) and Contaminated Estuarine Sediments along the Texas Coast. Values in PartsPer Million. 


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11 








Table 1.2. Representative Temperatures at Galveston, 1951-1980. 


Measurement 

Date 

Temperature 



CF) 

Average monthly low temperature 

February 

49 

Average monthly low temperature 

July 

78 

Average monthly high temperature 

February 

62 

Average monthly high temperature 

July 

88 


Source: Compiled from Larkin and Bomar, 1983 (8); Riggio and others, 1987 (9), and Schexnayder, 1987 
( 10 ). 


According to a classification developed principally on annual rainfall, the study area lies in an 
"Upper Coast" climate (9). Based on 1951-1980 records for this climatic division, the average annual 
precipitation at Galveston is about 44 inches. Most precipitation at this location occurs in early fall 
and late spring and coincides with the passage of frontal systems. Average annual precipitation is 
nearly balanced by the average annual gross lake evaporation rate, which is 45 inches. Mean annual 
sunshine, expressed as a percent of possible sunshine, is about 60 percent. 

Representative winter and summer temperatures at Galveston are shown in Table 2 (8). Because 
the Gulf of Mexico moderates the temperature in all seasons, the temperature inland has greater 
extremes. For example, the average monthly low temperature in February in Houston is nearly 44 °F 
(49 T in Galveston); the average monthly high temperature in July in Houston approaches 94 °F (88 °F 
in Galveston). Average winters in Galveston have only four days with a temperature below freezing 
and summers have an average of 13 days above 90 *F. The lowest recorded temperature is 8 °F in 1899; 
the highest temperature is 101 °F in 1932. At the Galveston Airport, mean relative humidity is 83 
percent at 6 a.m. and about 90 percent at 6 p.m. (10). Winters are mild, and summers are warm and 
humid; there is less daily temperature variation in summer. The bay area averages 335 growing days 
for local agriculture. 

The predominant winds for the year blow from the southeast (8). However, wind patterns for the 
summer are very different from winds patterns for the winter (Figure 6). In June through August, 
winds have mainly southern and eastern components. From December through February, north 
winds blowing in excess of 10 knots dominate, and alternate with lighter south winds. During "blue 
northers," winds up to 40 knots increase wave height, push several feet of water out of the bays, and 
tilt the level of the bay surface. Then oyster reefs commonly stand well above the water surface. 

The Texas climate has two phenomena that greatly skew average and mean climatic data— 
droughts and hurricanes. A serious drought has harmed some region in Texas each decade of the 20th 
Century: During 1950-1956 a major drought plagued every sector of Texas. A drought in the river 
basins supplying fresh water to the Galveston Bay System is potentially more devastating than 
drought within the bay system. The Texas Water Commission made a special study of droughts (9) 
between 1931 and 1985 to plan water needs better. A map (Figure 7) of the frequency of occurrence 
of six-month drought in Texas, 1931-1985, shows the basins to be less affected than most of Texas. 
However, 22 such droughts affected the West Fork of the Trinity River. If severe to extreme droughts 
are considered, only six to eight severe droughts occurred here, compared with more than 12 
droughts elsewhere (including Laguna Madre). 

Tropical storms or hurricanes strike the Texas coastline with a frequency of 0.67 storms per year 
(11). The amount of geomorphic adjustment or damage caused by these storms depends upon the 
approach speed, wind velocity, barometric pressure at the storm's eye, storm surge height, wave 
height, direction of approach to the coast, and total rainfall. Recorded maxima of these parameters 
are, respectively, 17 mph for an unnamed storm at Port O'Connor in 1929; 140 mph for Hurricane 
Beulah at Brownsville in 1967; 27.49 inches (lowest) at Port O'Connor for Hurricane Carla in 1961; 22 


12 







FREQUENCY OF SIX-MONTH 
EXTREME DROUGHTS 

More than 14 occurrences 


Figure 1.7. Frequency of occurrence of six-month 
droughts in Texas, after Riggio and others, 
1987(9). 


OA 9689 


300 mi 


400 km 


E 


EXPLANATION 



Wind speed (knots) 

I- 3 
4-7 
8-10 

II- 13 
14-18 


QA 9690 


Figure 1.6. Wind rose for summer (upper diagram) and winter 
(lower diagram) winds at Houston Intercontin¬ 
ental Airport, 1971-1980. Summer is June-Aug¬ 
ust; winter is December-February, after Larkenand 
Bomar (1983). Length of the bar in a rose indicates 
the percent of days per three months the wind blows 
from a given azimuth. 


13 






































Table 1.3. Tidal Ranges in the Galveston Bay System for 1988. 





Time 

Height 

Ranges 

Mean 


Position 

High 

Low 

High 

Low 

Mean 

Tide 

Location 

Nlat. 

W long. 

H.M.’ 

H.M. 1 

(ft) 

(ft) 

diurnal 

(fth 

Level 

(ft)’ 

Galveston Channel 

29*19’ 

94*48’ 

— 

— 

— 

— 

1.4 

0.7 

Texas City 

29*23’ 

94*53’ 

+0033 

+0041 

0.00 

0.00 

1.4 

0.7 

Clear Lake 

29*34’ 

95*04' 

+0605 

+0640 

0.64 

0.64 

0.9 

0.4 

Morgan Point 

29*41’ 

94*59’ 

+1021 

+0519 

0.71 

0.71 

1.0 

0.5 

Trinity Bay 

29*44’ 

94*42' 

+1039 

+0515 

0.71 

0.71 

1.0 

0.5 

East Bay 

29*31’ 

94*29' 

+0316 

+0418 

0.86 

0.86 

1.2 

0.6 

Christmas Bay 

29*05' 

95*10’ 

+0232 

+0231 

0.64 

0.64 

0.9 

0.4 

San Luis Pass 

Gulf of Mexico 

29*05' 

95*07’ 

-0009 

-0009 

0.86 

0.86 

1.2 

0.6 

(Galveston area) 

29*17 

94*47’ 

-0106 

-0106 

1.50 

1.50 

2.1 

1.1 


’H.M. = Hours and minutes to be added to or subtracted from the time of high or low water at 
a reference station. + = tide at subordinate station is later than at the reference station and 
should be added. - = tide is earlier and should be subtracted. 

’Mean diurnal range is the difference in height between mean higher high water and mean 
lower low water. 

’Mean tide level is a plane midway between mean low water and mean high water. 

Source: U.S. Department of Commerce tide tables, 1987. 


feet at Port Lavaca for Hurricane Carla in 1961; 40 feet at sea for Hurricane Carla in 1961; and 30 inches 
near Brownsville for four or five days during Hurricane Beulah in 1967. Saltwater flooding from 
Carla extended as much as 15 miles inland in the Galveston-Houston vicinity. Galveston has been the 
principal landfall site of four hurricanes since 1900; Hurricane Alicia in 1983 was the most recent (12). 

Bay Circulation 

Principal mechanisms that drive the circulation in the Galveston Bay System are prevailing 
winds, tides and freshwater inflow. Prevailing winds and normative speeds are documented above 
(Figure 6); salinity and nutrient gradients may be modeled, given a holistic understanding of the bay 
circulation system. 

Tides 

Tides are an important driving force in all bay systems; in the Galveston Bay System, tides are 
relatively weak (13). Tides cycle every 14 days. There are 14 days of one high and low tide followed 
by 14 days of two high tides and two low tides of different magnitudes. The tidal station inside the 
Galveston Channel records a mean annual tidal range of 1.4 feet, whereas the mean annual tidal range 
for the Gulf of Mexico at Galveston Pier is 2.1 feet (Table 3). The maximum tidal range in the bay for 
a 1988 spring tide is 2.4 feet. The tidal range decreases northward into upper Galveston and Trinity 
Bays, eastward in East Bay, and westward in West Bay as circulation becomes increasingly distant 
from the inlets. However, because of the location and orientation of the Intracoastal Waterway, tides 
appear tohave higher velocities than expected in East and West Bays. 

Approximately 80 percent of the tidal exchange between the Gulf of Mexico and the Galveston 
Bay System occurs through Bolivar Roads (13). Less than 20 percent of the tidal exchange occurs 


14 








Roads. The tide tables illustrate the slow progression of the tides between the inlets and the upper 
bay tidal stations (Table 3). 

Freshwater Inflow 

Not eveiy stream entering the bays has a stream gauge; consequently, Texas water agencies group 
the streams into basins in measuring and calculating freshwater inflow (15). Inflow into the Gal¬ 
veston Bay System is gauged for the Trinity and San Jacinto Rivers. Inflow is calculated for the minor 
basins composed of small streams; these basins are the San Jacinto-Brazos Coastal Basin, the San 
Jacinto-Trinity Coastal Basin, and the Trinity-Nueces Coastal Basin. From calculations for the years 
1941-1976, the average annual freshwater inflow to the Galveston Bay System from the two principal 
basins and three lesser basins was 11,340,000 acre-foot. For the same period, the maximum annual 
freshwater flow was 23,696,000 acre-foot in 1973, and the minimum annual inflow was 2,913,000 acre- 
foot in 1956, near the end of the worst Texas drought of this century. For the same years the freshwater 
inflow balanced against evaporation losses were, respectively, 22,290„000 and 1,321,000 acre-foot. 

Measurements of the average annual inflow and average monthly inflow of the major 
contributing stream, theTrinity River, show similar patterns for the years 1941-1976. Until 1970 there 
was a large difference in the fluctuation of flood stage and low stage; thereafter, the difference 
between high and low stages has been small. However, for the same time period the mean annual 
inflow equals about the same amount. The alteration of the inflow pattern correlates with the increase 
in upstream dams after the 1950 drought years. 

On the basis of exceedance frequencies for monthly freshwater inflows between 1941 and 1976 
(16), it was calculated that the Trinity River Basin supplies more than 70 percent of inflow during the 
wet months of December through June. The San Jacinto River Basin supplies about 18 percent and 
the San Jacinto-Brazos Coastal Basin supplies less than 2 percent. Inflows from the coastal basins that 
have ungauged streams are roughly calculated from the size, slopes and stream gradients of small 
streams. 

Salinities and Nutrients 

Circulation in the Galveston Bay System reflects bathymetry of the bays and tidal inlets, location 
and amounts of freshwater inflow, location and amounts of saltwater inflow, velocity and orientation 
of tides, bottom friction, wind speed and direction, rainfall history, and surface evaporation. Most 
of these variables are well known, as we described previously in this paper. However, because no 
current meters have been set in the major inlets for a long term, only brief temporal measurements 
of exchange in the inlets are available. In order to understand salinity changes and nutrient processes 
in Galveston Bay, the Texas Water Development Board has modeled tidal circulation, salinity 
changes and nutrient processes (16). The model simultaneously solves multiple tidal hydrodynamic 
equations over a rectangular grid of cells in a discrete fashion. 

Monthly vector plots of the net flow through each computational cell show similar circulation 
patterns for groups of months (16). In March, August (Figure 8) and October, the most evident 
circulation pattern in the Galveston Bay System was a northwesterly directed current in the Houston 
Ship Channel and a clockwise circulation in Trinity Bay moving along the eastern shore. The current 
in West Bay was predominantly directed in a northeasterly direction from San Luis Pass to the 
Galveston Ship Channel. In January, February, July, September, November and December, the 
current in the Galveston Ship Channel was directed southeastward, and the dominant flow in Trinity 
Bay rotated cou n terc lock wise along the northwestern shore. An internal current rotated counter¬ 
clockwise in West Bay with the net water movement from Bolivar Roads through the Galveston Ship 
Channel and through San Luis Pass via West Bay into the Gulf of Mexico. In April, May and June, 
months of largest freshwater inflow, a very strong southeasterly current prevails in the Houston Ship 
Channel. Trinity Bay flow is counterclockwise in April and May, but clockwise in June, and north¬ 
easterly moving currents dominate flow in West Bay during the same months. 

Simulated salinity gradients, calculated from the model, also display seasonality. The lowest 
salinities occur in June, whereas the highest salinities appear in August (Figure 8). In the spring and 
early summer (March, April, May and June) salinity is generally less than 5 ppt in Trinity Bay, 10 ppt 
in Galveston Bay, 25 ppt a t Bolivar Roads, 20 to 25 ppt in West Bay, and 10 to 15 ppt in East Bay. During 
these four months an intrusion of salt water is evident along and beside the Houston Ship Channel. 


15 




Figure 1.8. Simulated salinities in the Galveston Bay System, 1941-1976, under the influence of freshwater inflows for 
May (freshest) and August (most saline), and average monthly circulation patterns for same months, after 
Texas Water Development Board, 1982 (16). Top diagram is May; lower diagram is August. 


16 




















For the remainder of the year, the salinities are generally near 10 ppt in much of Trinity Bay, 10 ppt 
in upper Galveston Bay to 25 ppt near Bolivar Roads, less than 20 to 25 ppt west to east in West Bay, 
and 10 to 25 ppt east to west in East Bay. 

Nutrient gradients in the Galveston Bay System reflect the richer nutrient composition of the 
contributory freshwater streams and the nutrient-poor saline waters of the Gulf of Mexico (17). In 
addition, nutrients are generated and contributed by biochemical cycling in bayhead deltas as well 
as by marshes and nonpoint sources from agriculture. Magnitudes of freshwater inflows, winds, 
currents and biological activity complicate understanding the effects of nutrient processes at any one 
time. 

Measurements of water quality in the Trinity River upstream of the delta indicate that mean 
monthly organic nitrogen varies from 0.39 mg/L to 0.79 mg/L(16). Concentrations in the upper part 
of the Houston Ship Channel/Buffalo Bayou area, in contrast, ranged from 1.0 mg/L to greater than 
2.0 mg/L. Maps displaying average organic nitrogen from 1968 to 1987 show a gradient of concen¬ 
tration from greater than 0.5 mg/L in the upper reaches of the Houston Ship Channel to 0.5 mg/L 
to 0.2 mg/L down-channel and along the northwestern shore of Trinity Bay. Concentrations continue 
declining gulfward by several orders of magnitude, and there is a plume of 0.2 mg/L to 0.1 mg/L 
organic nitrogen flowing through Bolivar Roads. Both West Bay and East Bay have negligible organic 
nitrogen concentrations of less than 0.1 mg/L. 

In the same study period, average phosphate concentrations are more than 0.5 mg/L in north¬ 
western Trinity Bay, in the upper Houston Ship Channel, and in western Galveston Bay. Consid¬ 
erable dilution is evident near the Trinity River. West Bay has extremely low phosphate content, as 
does East Bay near Rollover Pass. 

The north-to-south nutrient gradients in the Galveston Bay System, encompassing more than two 
orders of magnitude and the plumes flowing out Bolivar Roads, deserve continued monitoring, as 
do seasonal concentrations approaching eutrophism. 

Active Processes 

The interconnected active processes of today are the same as those that occurred in past geologic 
time and that first formed the Galveston Bay System. Continuously changing magnitudes and rates 
of sediment influx, sea-level change (Figure 9), subsidence, faulting, and erosion and accretion are 
demonstrated by gains and losses of land, bay or Gulf. In contrast to active geologic processes, human 
activities rapidly alter or overwhelm the short-term effectiveness of some of the natural active pro¬ 
cesses in sculpting the bay system. 

Sediment Influx, Natural Subsidence and Sea-Level Change 

Sediment influx is significant where streams enter the bay system. Continuous sedimentation, in 
the absence of sea-level rise and subsidence, causes shoreline accretion and provides both stable land 
and nutrients for new marsh growth. Decreased rate of sediment influx with a concomitant rise of 
sea level or increased subsidence produces shoreline erosion and removes marsh. 

Records from the Trinity River near the delta from 1935 to 1980 show a continuous decline in the 
suspended sediment load beginning in 1950, coincident with the increased dammed reservoir 
capacity (17). The upstream reservoirs trap not only bed load but also a considerable fraction of the 
suspended load of streams. For the interval (1904-1980), combined tidal records at Galveston (18) 
show a relative sea-level rise of nearly 1.5 feet (Figure 9). 

Recently the bayhead deltas of the principal streams feeding Galveston Bay have begun to lose 
land and elevation. The loss of land between 1956 and 1979 reflects decreased influx of sediment and 
natural subsidence related to compaction of deltaic sediments; a rise of sea level, although possibly 
involved, is not documented. Figure 9 illustrates the loss of fluvial woodlands, swamps and marshes 
in the San Jacinto delta area (7). 

As noted previously, subsidence is a continuing natural process in which thick sedimentary 
deposits compact over long periods of time. An overprint of additional subsidence, in excess of 10 
feet at some locations in the Houston metropolitan area, has occurred since 1906 as a result of with¬ 
drawal of subsurface fluids. A large bowl-shaped area more than 80 miles in diameter has subsided 
principally because of ground water removal (19). Subsidence along the bay at Clear Lake Bayou near 


17 



Figure 1.9. Relative sea level measured at Pier 21 in Galveston, 1910 to 1980. 

principally because of groundwater removal (19). Subsidence along the bay at Clear Lake Bayou near 
the NASA Space Center measures 5.5 feet. A housing subdivision near Baytown is now submerged 
beneath several feet of bay water, thus contributing the complex chemicals of developed properties 
and roads to the bay system. More than 30 percent of the park land (130 acres) subsided into the bay 
at the San Jacinto Battleground. Recently, the subsidence rate in these areas has decreased, in part 
related to better management of groundwater pumping regulated by the Harris County Subsidence 
District. 

Not all man-induced subsidence relates to ground-water pumpage; some subsidence clearly 
relates to oil and gas production, especially as production includes reservoir water as well as oil and 
gas. In the Galveston Bay area a larger net subsidence represents the integration of pumping ground 
water and petroleum. The two localities of maximum subsidence, Pasadena and Baytown, probably 
experienced exploitation of both fluids. 

Faults 

Faults related to the original deposition of sediments and to subsequent formation of salt domes 
persist as planes of weakness and remain active today on the land surface (19) and on the seafloor of 
the bays and Gulf (7). Depositional and compactional faults generally form arcuate trends, more than 
20 miles long, subparallel to the Gulf shoreline. Faults associated with salt diapirs typically form a 
peripheral complex of horsts and grabens constructed of short straight faults with a radial pattern. 
Natural escarpments at the surface, which reflect the vertical offsets of the faults, are generally less 
than 3 feet high. The natural fault scarps may be frequently very subtle features. 

Because natural faults are commonly planes of weakness susceptible to further displacement 
from subsidence, larger surficial offsets and high fault scarps may occur. Elevation differences on 
each side of the Hockley escarpment measure as much as 45 feet in 1 mile. Detrimental effects of active 
faults underneath transportation routes and buildings on land and under or along pipelines in the 
bay can be significant. 

Erosion and Accretion 

Erosion is a predominant, nearly ubiquitous, process around Galveston area bays and on Gulf 
beaches (Table 4) (17,18), except where deltation or spits naturally develop. This erosion and conse¬ 
quent land loss represents the summation of (1) sea-level rise, (2) a wave-dominated shallow bay, (3) 
episodic tropical storms and northers, and (4) minor subsidence. Land losses along the Gulf shoreline 
reflect a deficit in sediment supply and relative sea-level rise or compactional subsidence (18). High¬ 
est rates of natural accretion occur at the bayhead delta of the Trinity River, where the shoreline 
advanced as much as 42.6 feet per year between 1851 and 1982. 

The largest rates of accretion or erosion are invariably related to human activities. Inordinately 


18 




Table 1.4. Erosion and Accretion Rates from Historical Monitoring of Shorelines of the 
Galveston Bay System. 


Bay Locations 



1850-52 to 1930 

1930 to 1982 

1850-52 to 1982 


No. of 

Rate 

No. of 

Rate 

No. of 

Rate 


stations 

(ft/yr) 

stations 

(ft/yr) 

stations 

(ft/yr) 

Trinity Bay 

66 

-1.8 

60 

0.9 

60 

-0.7 

E. Trinity Bay 

Lake Anahuac 

26 

-3.0 

25 

-1.8 

25 

-2.6 

(does not include Trinity delta) 9 

-2.9 

6 

+0.6 

e 

-0.9 

Trinity Delta 

10 

+3.9 

9 

+7.2 

9 

+5.8 

W. Trinity Bay 

21 

-2.6 

20 

-2.3 

20 

-2.3 

Galveston Bay 

57 

-2.2 

55 

-4.2 

55 

-3.0 

West Bay 

106 

-1.6 

98 

-2.4 

84 

-2.0 

N. West Bay 

23 

-2.5 

7 

-3.8 

7 

-3.6 

Chocolate Bay 

15 

-1.0 

15 

-2.4 

15 

-1.6 

W. West Bay 

4 

-6.5 

7 

-6.3 

4 

-7.0 

W. peripherals 

30 

-1.3 

29 

-1.5 

27 

-1.6 

S. West Bay 

34 

-0.8 

40 

-2.1 

31 

-1.5 

East Bay 

54 

-1.8 

48 

-3.2 

47 

-2.1 

S. East Bay 

30 

-2.1 

24 

-3.7 

23 

-2.3 

N. East Bay 

24 

-1.4 

24 

-2.8 

24 

-1.9 




Gulf Locations 




1883 to 1930 

1930 to 1955 

1883 to 1974 


No. of 

Rate 

No. of 

Rate 

No. of 

Rate 


stations 

(ft/yr) 

stations 

(ft/yr) 

stations 

(ft/yr) 

Bolivar Peninsula 

16 

-0.3 

19 

+4.1 

16 

0.1 


1850 to 1930 

1930 to 

1956 

1838 to 

1970 


No. of 

Rate 

No. of 

Rate 

No. of 

Rate 


stations 

(ft/yr) 

stations 

(ft/yr) 

stations 

(ft/yr) 

Galveston Island 

28 

-3.3 

28 

+45 

28 

-2.4 


Source: Paine and Morton, 1986 (17) and Morton, 1974 and 1975 (18). 


high rates of shoreline accretion adjacent to Bolivar Roads, as much as 28 feet per year on Bolivar 
Peninsula and 48 feet per year on eastern Galveston Island, were not included in Table 4; coastal 
engineering structures (e.g., jetties) artificially enhance accretion rates. Similarly, maximum losses of 
land measured in the bays occur in areas of maximum man-induced subsidence. 

Rates of erosion and accretion for the Galveston Bay System were calculated from historical 
monitoring of shorelines for long time periods. Although effects of hurricanes are averaged into these 
calculations, the magnitude of work accomplished by a hurricane is not apparent. Since 1900, four 
hurricanes have centered on Galveston, in 1900,1947,1959 and 1983 (11). The unnamed 1900 storm 
was the most severe (10)—having an approach speed of 10 mph, maximum winds of 125 mph, 
barometric pressure of 27.64 inches, and a storm surge height of 20 feet. No maps or aerial photo¬ 
graphs are available to document erosion and accretion for that storm. However, Carla in 1961 had 
nearly the same intensity in all categories. A gulfward facing shoreline eroded as much as 800 feet 
and about 500 feet of sand accreted to the rear shore of the barrier island (20). No bay shoreline 
measurements were found. 


19 





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CP 

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O 
O ^ 

<4— U 
0) 

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< x c/> 
U CD -Q 

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- § 2 
CO O 


O 

K 


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20 


Figure 1.10. Losses of fluvial rvetlands and marshes in the San Jacinto Estuary, between 1954 and 1979, after White and others, 1985 (7). 






























































































Erosion and accretion of the Galveston Bay System when Hurricane Alicia struck in 1983 are well 
documented (12). Compared with Carla, a class IV storm, Alicia was a class III storm (12). In this 
storm, the eye passed over San Luis Pass. The beach level of West Beach landward of the prestorm 
vegetation line was lowered about 3 feet by erosion, and the average vegetation-line retreat was 
nearly 80 feet. Loss of sand for this part of the prestorm beach terrain was 883,750 yards 3 . The largest 
possible erosion in the shortest time from a potential hurricane needs to be part of future Galveston 
Bay management. Beyond the significance of geologic processes, the effects of Hurricane Alicia on 
beachfront properties are especially important to landowners and coastal managers. 

Recommendations 

Although we know much about the physical setting of the Galveston Bay System, conditions that 
impact people should be widely and repeatedly monitored. For example, the geology and geochem¬ 
istry of Galveston Bay was sampled only once, in 1976. Resampling and reanalyses are needed to 
examine human impacts on the chemistry of Galveston Bay further. Continued monitoring of water 
chemistry, salinities and nutrients is the key to the healthy existence of the bays and their animal 
populations. 

Modem high-resolution seismic profiles of the shallow bay sediments would provide valuable 
information for permitting future constmction. Improved physical measurements of water circula¬ 
tion, especially currents and tides, would enhance bay system management. No long-standing 
current meters have ever been emplaced at the inlets; salinity and nutrient gradients indicate the need 
for long-term monitoring of currents in the Houston Ship Channel and at other significant sites. The 
EPA predictions of expected (drastic?) sea-level rise need immediate attention; ground releveling 
and tide gauge measurements are required to predict the response of various types of shorelines to 
increased sea-level changes. 

Shoreline changes and sediment influxes that reflect losses of both private property and public 
wetlands need a new cycle of monitoring in order to develop a holistic management approach. We 
need additional information on the impacts of major storms for planning emergency responses, and 
we need to improve predictions of coastal evolution with respect to potential sea-level rise. 

Selected References 

1. Salvador, Amos, 1987. LateTriassic-JurassicPaleogeography and Origin of Gulf of Mexico Basin; 
American Association of Petroleum Geologists Bulletin, v. 71, pp. 419-451. 

2. Murray, G.E., Rahman, A.U., and Yarborough, Hunter, 1983. Introduction to the Habitat of 
Petroleum, Northern Gulf Coastal Province; Gulf Coast Section, Society of Economic 
Paleontologists and Mineralogists Foundation, 4th Annual Research Conference, pp. 34-38. 

3. Morton, R.A., Jirik, L.A. and Foote, R.Q., 1985. Structural Cross Sections, Miocene Series, Texas 
Continental Shelf; The University of Texas at Austin, Bureau of Economic Geology, 8 p., 3 figs., 
17 pis. 

4. Galloway, W.E., Ewing, T.E., Garrett, C.M., Tyler, N., and Bebout, D.G., 1983. Atlas of Major 
Texas Oil Reservoirs; The University of Texas at Austin, Bureau of Economic Geology, Special 
Report, 139p. 

5. Fisher, W.L., McGowen, J.H., Brown, L.F., Jr., and Groat, C.G., 1972. Environmental Geologic 
Atlas of the Texas Coastal Zone—Galveston-Houston Area; The University of Texas at Austin, 
Bureau of Economic Geology, 91p; and -Fisher, W.L., McGowen, J.H. and Proctor, C.V., Jr. 
(Barnes, V.E.), 1982. Geologic Atlas of Texas—Houston Sheet; The University of Texas at Austin, 
Bureau of Economic Geology, map. 

6. Bernard, H.A., Major, C.F., Jr., Parrott, B.S. and LeBlanc, R.J., Sr., 1970. Recent Sediments of 
Southeast Texas—A Field Guide to the Brazos Alluvial and Deltaic Plains and the Galveston 
Barrier Island Complex; The University of Texas at Austin, Bureau of Economic Geology, 
Guidebook 11,132 p. 

7. McGowen, J.H. and Morton, R.A., 1979. Sediment Distribution, Bathymetry, Faults and Salt 
Diapirs on the Submerged Lands of Texas; The University of Texas at Austin, Bureau of Economic 


21 


Geology, Special Publication, 31 p; and White, W.A., Calnan, T.R., Morton, R.A., Kimble, R.S., 
Littleton, T.G., McGowen, J.H., Nance, H.S., and Schmedes, K.E., 1985. Submerged Lands of 
Texas, Galveston-Houston Area: Sediments, Geochemistry, Benthic Macroinvertebrates, and 
Associated Wetlands; The University of Texas at Austin, Bureau of Economic Geology, Special 
Publication, 145p. 

8. Larkin, T.J. and Bomar, G.W., 1983. Climatic Atlas of Texas; Texas Department of Water 
Resources, LP-192,151p. 

9. Riggio, R.F., Bomar, G.W. and Larkin, T.J., 1987. Texas Drought: Its Recent History; Texas Water 
Commission, LP 87-04, 74p. 

10. Schexnayder, Deanna, 1987. The Climates of Texas Counties; The University of Texas at Austin, 
Bureau of Business Research, Natural Fibers Information Center, and Texas A&M University, 
Office of the State Climatologist, 569p. 

11. Hayes, M.O., 1967. Hurricanes as Geological Agents: Case Studies of Hurricanes Carla, 1961, and 
Cindy, 1963; The University of Texas at Austin, Bureau of Economic Geology, Report of 
Investigations No. 61,54p; and Brown, L.F., Jr., Morton, R. A., McGowen, J.H., Kreitler, C. W., and 
Fisher, W.L., 1974. Natural Hazards of the Texas Coastal Zone; The University of Texas at Austin, 
Bureau of Economic Geology, Special Publication, 13p. 7 maps. 

12. Morton, R.A. and Paine, J.G., 1985. Beach and Vegetation-Line Changes at Galveston Island, 
Texas: Erosion, Deposition and Recovery from Hurricane Alicia; The University of Texas at 
Austin, Bureau of Economic Geology, Geological Circular No. 85-5, 39p. 

13. U.S. Department of Commerce, 1987. Tide current tables for 1988, Atlantic Coast of North 
America; National Oceanic and Atmospheric Administration, National Ocean Survey, 288p. 

14. Shew, D.M., Baumann, R.H., Fritts, T.H., and Dunn, L.S., 1981. Texas Barrier Island Region 
Ecological Characterization: Environmental Synthesis Papers; Washington, D.C., U.S. 
Department of Interior, Fish and Wildlife Service, Office of Biological Services, FWS/OBS-81 / 
32.413p. 

15. Texas Department of Water Resources, 1981. Trinity-San Jacinto Estuary; a Study of the Influence 
of Freshwater Inflows; Austin, Texas, Texas Water Development Board and Texas Water Com¬ 
mission, LP-113, 383p. 

16. Texas Department of Water Resources, 1982, Trinity-San Jacinto Estuary: An Analysis of Bay 
Segment Boundaries, Physical Characteristics and Nutrient Processes; Austin, Texas, Engin¬ 
eering and Environmental Systems Section of Planning and Development Division, LP-86,77p. 

17. Paine, J.G. and Morton, R.A., 1986. Historical Shoreline Changes in Trinity, Galveston, West and 
East Bays, Texas Gulf Coast; The University of Texas at Austin, Bureau of Economic Geology, 
Geological Circular 86-3,58p. 

18. Morton, R.A., 1974. Shoreline changes on Galveston Island (Bolivar Roads to San Luis Pass), An 
Analysis of Historical Changes of the Texas Gulf Shoreline. The University of Texas at Austin, 
Bureau of Economic Geology, Geological Circular 74-2,34p; and Morton, R.A., 1975. Shoreline 
Changes between Sabine Pass and Bolivar Roads, An Analysis of Historical Changes of the Texas 
Gulf Shoreline; The University of Texas at Austin, Bureau of Economic Geology, Geological 
Circular 75-6,43p. 

19. Harris-Galveston Coastal Subsidence District, 1987. Subsidence '87, Brochure, 13p; Kreitler, 
C.W., Guevara, E., Granata, G., and McKalips, D., 1977. Hydrogeology of Gulf Coast Aquifers; 
The University of Texas at Austin, Bureau of Economic Geology, Geological Circular 77-4,18p; 
and Kreitler, C.W., 1976, Lineations and Faults in the Texas Coastal Zone; The University of Texas 
at Austin, Bureau of Economic Geology Report of Investigations No. 85,32p. 

20. McGowen, J.H., Groat, C.G., Brown, L.F., Jr., Fisher, W.L., and Scott, A.J., 1970. Effects of 
Hurricane Celia—A Focus on Environmental Geologic Problems of the Texas Coastal Zone; The 
University of Texas at Austin, Bureau of Economic Geology Geological Circular 70-3,35 p; and 
McGowen, J.H. and Brewton, J.L., 1975. Historical Changes and Related Coastal Processes, Gulf 
and Mainland Shorelines, Matagorda Bay Area, Texas; TheUniversity of Texas at Austin, Bureau 
of Economic Geology, Special Publication, 72p. 


22 


Biological Components 
of Galveston Bay 

Peter F. Sheridan, R. Douglas Slack, Sammy M. Ray, Larry W. McKinney, 
Edward F. Klima, Thomas R. Calnan 1 


Distribution and Abundance 


Estuarine Vegetation 

PETER F. SHERIDAN—The plant life of Galveston Bay includes phytoplankton in the water 
column, benthic microflora, macroalgae, submerged aquatic vegetation and emergent vascular 
plants. Some groups are so dense that they are major sources of physical structure for other estuarine 
organisms, while some groups are major producers of organic materials for assimilation by 
consumers. Other functions of vegetation include refuge from predators, maintenance of water 
quality by filtering runoff and tidal inputs, and shoreline stabilization. 

Phytoplankton—The phytoplankton of upper Galveston and Trinity Bays is composed of at least 
132 species, including diatoms (54 taxa), green algae (45 taxa), blue-green algae (14 taxa), dinoflagel- 
lates (9 taxa), euglenoids (7 taxa), cryptophy tes (2 taxa), and golden-brown algae (1 taxon) (1). Many 
of these species, particularly the green algae, are freshwater forms entering via river discharge. Over 
an annual cycle (September 1975-August 1976), the mean percentage of the standing crop for each 
division was found to be diatoms (41.6 percent), green algae (24.2 percent), blue-green algae (23.0 
percent), dinoflagella tes (5.9 percent), euglenoids (2.6 percent), and others (2.7 percent). Major peaks 
in phytoplankton density occurred in late winter and mid-summer. The winter peak was due to the 
diatoms Skeletonema costatumand Cyclotellamenenghiniana, while the summer peak in densities 
was due to a bloom of the blue-green Oscillatoria sp. As a group, diatoms were the dominant 
phytoplankters in November, December and February-June (Skeletonema and Cyclotella in cold 
months, Nitzschia closterium, Navicula abunda and Thalassionema nitzschoides in warmer 
months). Green algae were a consistent 20 to 30 percent of the monthly standing crops, and 
Ankistrodesmus sp. bloomed in September-October. Blue-green algae were relatively abundant 
July to October, and a bloom of Oscillatoria in July represented 70 percent of the standing crop. The 
dinoflagellate Prorocentrum sp. comprised 45 percent of the total density in January. Euglenoids 
such as Euglena spp. and Eutreptia spp. were relatively abundant in May and August. Lower salinity 
stations were dominated by blue-green and green algae while high salinity sites were dominated by 
diatoms. 

Similar studies on phytoplankton distribution and abundance have not been conducted in lower 
Galveston, East or West Bays. 

Benthic Micro flora—Components of the benthic microflora have been examined in a descriptive 
sense (2-4), but little information on temporal or spatial distribution is available. Thirty-three genera 


’Peter F. Sheridan and Edward F. Klima represent the National Marine Fisheries Service; R. Douglas Slack, 
Texas A&M University; Sammy M. Ray, Texas A&M University at Galveston; Larry D. McKinney, Texas Parks 
and Wildlife Department; Thomas R. Calnan, Bureau of Economic Geology, The University of Texas at Austin. 


23 



Table 2.1. Benthic Algae Collected from Bay Sediments (2) and Beach Sands (4) in the 
Galveston Bay System. 

Green Algae 

Blue-green Algae 

Diatoms 

Bracteacoccus 

Anabaena 

Achnanthes (2) 

Characium 

Anacystis 

Actinoptychus (3) 

Chlamydomonas 

Aphanocapsa 

Amphora (3) 

Chlorosarcina 

Aphanothece 

•Coscinodiscus (10) 

Chlorosarcinopsis 

Calothrix 

•Cydotella (3) 

Chlorococcum 

Gloeocapsa 

Diatoma (1) 

Cylindrocystis 

Lyngbya 

•Diploneis (4) 

Eremosphaera 

Myxosarcina 

Epithemia (1) 

Gloeocystis 

Nostoc 

Eunotogramma (1) 

Hormidium 

Oscillatoria 

Mastogloia (1) 

Oedocladium 

Schizothrix 

Melosira (2) 

Pleurastrum 

Spirulina 

Navicula (4) 

Radiosphaera 

Synechococcus 

Nitzschia (9) 

Stichococcus 

Synechocystis 

Opephora (1) 

Tetracystis 

Xenococcus 

Pinnularia (1) 

Tetraedon 


Pleurosigma (4) 
Rhopalodia (2) 
•Skeletonema (1) 
Stenopterobia (1) 

Crvptophvtes 

Euglenpphytes 

Stephanodiscus (1) 

Cryptomonas 

Euglena 

Surirella (1) 

Synedra (1) 

(n) = number of species in genus, if given 
* = most abundant 



of algae were identified from Galveston Island beach sands, and 22 genera (56 species) of diatoms 
were identified from bay sediments (Table 2.1). The diatoms Coscinodiscus, Diploneis, Cydotella 
and Skeletonema were noted as being very abundant (2), the latter two genera also dominating the 
phytoplankton as noted previously. Diatoms were the main component of the benthic microflora in 
waters deeper than 0.5 m, while blue-green algae dominated the shallow water and tidal flats (3). 
Algal densities could not be related to depth, sediment type. Eh, pH or salinity. 

Macroalgae—There has been no survey of macroalgal types over the whole bay system. Several 
faunal surveys (9,13,24) noted that, where present, the macroalgae is represented by Enteromorpha, 
Ectocarpus, Dictyota, Sargassum, Polysiphonia and Gracilaria. The major study of macroalgae was 
limited to Galveston Island proper (46), finding 19 genera and 28 species over a two-year period 
(Table 2.2). The gulf shore community is composed of Cladophora, Bryocladia and Ceramium in 
summer and shifts to Enteromorpha, Bangia and Gelidium in winter. The bay shore community is 
barren in the summer and is primarily Enteromorpha and Ectocarpus during winter. The flora is 
considered depauperate relative to other Gulf estuaries. 

Submerged aquatic vegetation—Submerged aquatic vegetation is limited in areal extent. On the 
Trinity River delta, the submerged freshwater plants Vallisneria americana (tapegrass) and Sagit- 


24 









Table 2.2. Benthic Macroalgae of Galveston Island Grouped by Maximum Growth Per- 
iods(46). 

Summer-Fall 

Winter-Spring 

Indeterminant 
(not enough date) 

Bryocladia cuspidata 

Ectocarpus siliculosus 

Dictyota dichotoma 

Ceramium strictum 

Petalonia fascia 

Gracilaria foliifera 

Cladophora dalmatica 

Enteromorpha dathrata 

Sargassum fluitans 

Cladophora linum 

Enteromorpha flexuosa 

Sargassum natans 

Polysiphonia gorgoniae 

Enteromorpha lingulata 

Vaucheria sp. 

Polysiphonia denudata 
Polysiphonia tepida 

Spyridia filamentosa 
Chaetomorpha linum 
Erythrocladia subintegra 
Erythrotrichia carnea 

Goniotrichum alsidii 

Achrochaetium sp. 

Enteromorpha prolifera 

Ulva lactuca 

Gelidium crinale 

Bangia fuscopurpurea 
Polysiphonia subtilissima 



taria kurziana (strap-leaf) are currently found in mixed stands (5). Vallisneria has also been found 
in the Chocolate Bay area off West Bay (24). Extensive Ruppia maritima (widgeon grass) beds were 
once located in shallow marginal waters of Trinity Bay and upper Galveston Bay (6-8). East Bay was 
found to be devoid of submerged vegetation (9). Ruppia was also scattered in various embayments 
along lower Galveston Bay and West Bay (10-13). Western West Bay, Christmas Bay and Bastrop Bay 
harbored seagrass beds dominated by Halodule wrightii (shoal grass) and lesser amounts of 
Thalassia testudinum (turtle grass) and Halophila engelmannii (13, 14). The areal extent of 
submerged vegetation has apparently declined from approximately 21 km 2 around 1960 (6-8,12) to 
<1 km 2 by 1979 (15). There have been no studies of seasonal growth or distribution of submerged 
vegetation in the Galveston Bay system, and no actual bay-wide site surveys for species composition 
and distribution. 

Marshes, woodlands and swamps—Emergent vegetation can be classified as salt, brackish or 
freshwater marshes, fluvial woodlands and swamps. These wetlands are large-scale contributors to 
estuarine productivity in terms of particulate matter, nutrients, structure, protection and substrate. 
Salt marshes cover an estimated 140 km 2 (12). Species such as Spartina alterniflora, Batis maritima, 
Salicornia spp. and Juncus roemerianus are most common in the more frequently flooded areas, 
while Borrichia frutescens, Monanthochloe littoralis, Distichlis spicata, Suaeda spp., Iva spp. and 
Aster spp. are less common (Table 2.3). Spartina alterniflora is the dominant plant in subsiding salt 
marshes due to almost constant flooding. Brackish marshes (230 km 2 ; 12) are of moderate salinity 
regimes (1 to 18 ppt) but are flooded by storm tides from the bay and by freshwater inundation from 
rainfall and runoff, thus they have a mixture of vegetation types (Table 2.3). Plants frequently 
occurring in fresher areas include Scirpus maritimus, S. califomicus and S. americanus, Alternath- 
era philoxeroides, Bacopa monnieri, Typha spp., Paspalum lividum and Phragmites australis, 
while plants in the more saline brackish marshes include Spartina patens and S. spartinae, Scirpus 
olneyi and S. maritimus, Paspalum vaginatum, Juncus roemerianus and species from higher salt 
marshes. Lower elevation brackish marshes are dominated by Scirpus, Typha, Eleocharis and 
Bacopa, whereas in higher elevation brackish marshes Spartina spartinae and S. patens are more 
common. Fresh marshes are generally beyond all salt water intrusion except during hurricane surges. 
There are approximately 40 km 2 of fresh marshes, primarily in the Trinity and San Jacinto River 
systems (12). Low fresh marshes are characterized by Typha spp., Scirpus americanus and S. 


25 







Table 2.3. Typical Plants Found in Galveston Bay Wetland Environments (15). 


Salt Marsh 


Spartina alterniflora 

smooth cord- 
grass 

Batis maritima 

saltwort 

Salicornia virginica 

glasswort 

Salicornia bigelovii 

glasswort 

Distichlis spicata 

seashore salt- 
grass 

Borrichia frutescens 

sea-oxeye 

Monanthochloe littoralis 

shoregrass 

Juncus roemerianus 

needle rush 

Suaeda sp. 

seablite or 
seepweed 

Lycium carolinianum 

Carolina 

wolfberry 

Spartina spartinae 

gulf cordgrass 

Spartina patens 

marshhay 

cordgrass 

Iva frutescens 

bigleaf 

sumpweed 

Iva angustifolia 

narrowleaf 

sumpweed 

Limonium nashii 

sea-lavender 

Scirpus maritimus 

salt-marsh 

bulrush 

Sporobolus spp. 

dropseed 

Sesuvium portulacastrum 

sea purslane 

Heliotropium curassavicum salt heliotrope 

Brackish Marsh 

Spartina spartinae 

gulf cordgrass 

Spartina patens 

marshhay 

cordgrass 

Borrichia frutescens 

sea-oxeye 

Distichlis spicata 

seashore 

saltgrass 

Monanthochloe littoralis 

shoregrass 

Scirpus maritimus 

salt-marsh 

bulrush 

Scirpus americanus 

three-square 

bulrush 

Scirpus califomicus 

California 

bulrush 

Scirpus olneyi 

Olney bulrush 

Altemanthera philoxeroides alligatorweed 

Typha domingensis 

narrowleaf 

cattail 


Typha latifolia 

common cattail 

Spartina cynosuroides 

big cordgrass 

Phragmites australis 

common reed 

Eleocharis parvula 

dwarf 

spikerush 

Cyperus spp. 

flatsedge 

Enchinochloa crusgalli 

barnyard grass 

Leptochloa spp. 

sprangletop 

Bacopa monnieri 

coastal 

waterhyssop 

Aster tenuifolius 

saline aster 

Aster subulatus 

saltmarsh aster 

Aster spinosus 

spiny aster 

Paspalum lividum 

longtom 

Paspalum vaginatum 

seashore 

paspalum 

Setaria geniculata 

knotroot 

bristlegrass 

Zizaniopsis miliacea 

giant cutgrass 

Solidago sempervirens 

seaside 

goldenrod 

Baccharis halimifolia 

groundsel bush 

Iva frutescens 

bigleaf 

sumpweed 

Iva angustifolia 

narrowleaf 

sumpweed 

Iva annua 

seacoast 

sumpweed 

Sesuvium portulacastrum 

sea purslane 

Salicornia spp. 

glasswort 

Limonium nashii 

sea-lavender 

Juncus roemerianus 

needle rush 

Lycium carolinianum 

Carolina 

wolfberry 

Sporobolus spp. 

dropseed 

Fimbristylis castanea 

fimbry 

Hydrocotyle spp. 

pennywort 

Fresh Marsh 

Spartina spartinae 

gulf cordgrass 

Typha latifolia 

common cattail 

Typha domingensis 

narrowleaf 

cattail 

Scirpus americanus 

three-square 

bulrush 


26 








Scirpus californicus 

California 

bulrush 

Paspalum lividum 

longtom 

Eleocharis spp. 

spikesedge 

Cyperus spp. 

flatsedge 

Alternanthera philoxeroides alligatorweed 

Juncus spp. 

rush 

Ludwigia spp. 

seedbox 

Sagittaria spp. 

arrowhead 

Pontederia sp. 

pickerelweed 

Polygonum spp. 

knotweed 

Phragmites australis 

common reed 

Bacopa monnieri 

waterhyssop 

Echinodorus spp. 

burrhead 

Eichhornia crassipes 

water hyacinth 

Rhynchospora sp. 

beakrush 

Fimbristylis spp. 

fimbry 

Echinochloa crusgalli 

barnyard grass 

Leptochloa spp. 

sprangletop 

Spartina patens 

marshhay 

cordgrass 

Lemna spp. 

duckweed 

Hydrocotyle spp. 

marsh penny¬ 
wort 

Zizaniopsis miliacea 

southern 

wildrice 

Sesbania drummondii 

rattlebush 

Baccharis halimifolia 

groundsel bush 

Cephalanthus occidentalis 

buttonbush 

Salix nigra 

black willow 

Transitional Areas 

Spartina spartinae 

gulf cordgrass 

Cynodon dactylon 

bermudagrass 

Borrichia frutescens 

sea-oxeye 

Aster spinosus 

spiny aster 

Paspalum monostachyum 

gulfdune 

paspalum 

Paspalum lividum 

longtom 

Panicum spp. 

panicum 

Rhynchospora spp. 

beakrush 

Andropogon virginicus 

broomsedge 

bluestem 

Andropogon glomeratus 

bushy bluestem 

Iva annua 

seacoast 

sumpweed 

Aristida spp. 

threeawn 

Setaria spp. 

bristlegrass 

Helianthus spp. 

sunflower 

Sorghum halepense 

johnsongrass 


Cassia fasciculata 

partridge pea 

Cyperus spp. 

flatsedge 

Eleocharis spp. 

spikesedge 

Scirpus spp. 

bulrush 

Croton spp. 

doveweed 

Spartina patens 

marshhay 

cordgrass 

Baccharis halimifolia 

groundsel bush 

Sesbania drummondii 

rattlebush 

Fluvial Woodlands 

Salix nigra 

black willow 

Celtis spp. 

hackberry/ 

sugarberry 

Fraxinus spp. 

ash 

Ulmus crassifolia 

cedar elm 

Ulmus americana 

American elm 

Quercus aquatica 

water oak 

Quercus lyrata 

overcup oak 

Quercus phellos 

willow oak 

Quercus stellata 

post oak 

Quercus virginiana 

live oak 

Liquidambar styraciflua 

sweetgum 

Ilex vomitoria 

yaupon 

Cephalanthus occidentalis 

buttonbush 

Sapium sebiferum 

Chinese tallow 

Pinus taeda 

loblolly pine 

Carya aquatica 

water hickory 

Carya illinoensis 

pecan 

Populus deltoides 

cottonwood 

Plantanus occidentalis 

American 

sycamore 

Planera aquatica 

water elm 

Acacia farnesiana 

huisache 

Parkinsonia aculeata 

retama 

Tamarix gallica 

salt cedar 

Sabal minor 

dwarf palmetto 

Taxodium distichum 

bald cypress 

Acer negundo 

boxelder 

Swamp 

Taxodium distichum 

bald cypress 

Planera aquatica 

water elm 

Carya aquatica 

water hickory 

Cephalanthus occidentalis 

buttonbush 


27 







californicus, Phragmites australis, Eleocharis spp., Cyperus spp., Juncus spp., Ludwigia sp., 
Sagittaria spp. and Paspalum lividum (Table 2.3) (1, 15). Higher fresh marshes are typified by 
Spartina spartinae, Paspalum spp.. Polygonum spp., Panicum spp., Borrichia, Rhynchospora 
macrostachya, Fimbristylis sp.. Aster spp. and Sesbania drummondii. Many species of Spartina 
exhibit broad salinity tolerances and are found in several categories of marsh. Fluvial woodlands 
along floodplains cover 450 km 2 (12) and support a variety of water-tolerant trees and shrubs (Table 
2.3), including Fraxinus spp., Salix nigra, Ulmus spp., Celtis spp., Carya spp. and Quercus spp. 
Swamps containing saturated soils or nearly permanent standing water comprise 50 km 2 (12) and are 
dominated by Taxodium distichum (Table 2.3). Additional information on wetland plants is also 
available (16). 

Between wetland surveys of 1956 and 1979, several changes were noted in vegetation patterns in 
the estuary: (1) expansion of open water into former marshes and woodlands; (2) expansion of 
marshes along the bay side of barrier islands into prior tidal flats; (3) formation of wetlands farther 
up creek valleys; (4) landward expansion of existing marshes; (5) reduction of submerged vegetation; 
and (6) reduction or modification of wetlands by human activities (15). Of primary concern are the 
losses of 63 km 2 of fresh marsh and 42 km 2 of salt and brackish marshes during this period. These 
losses are ascribed to such activities as channelization, impoundments, filling and subsidence 
associated with subsurface petroleum or water extraction. 

Invertebrates 

Invertebrates within the Galveston Bay system are discussed by component groups such as zoo¬ 
plankton, benthos, and mobile and sessile macrofauna. While there have been a number of studies 
of invertebrates in this area, there are no synoptic zooplankton or macro faunal surveys on a bay-wide 
basis. 

Zooplankton—A 12-month study of zooplankton in the upper Galveston and Trinity Bay areas 
(1) revealed 70 species representing nine phyla. The most abundant plankters included copepods 
(primarily Acartia tonsa, followed by Labidocera, Cyclops and Oithoina) and barnacle nauplii 
(Balanus spp.); in fact, these two phyla plus a mixed assemblage of copepod nauplii and copepodites 
represented >70 percent of the zooplankton in 11 of 12 months. Other phyla included rotifers 
(Asplancha, Brachionus, Keratella), dinoflagellates (Noctiluca scintillans) and larvaceans 
(Oikopleura). Zooplankton densities peaked in April (dominated by copepod nauplii and Nocti¬ 
luca) and August (Acartia and copepod nauplii). Barnacle nauplii were most dense in late winter- 
early spring. Fluctuations in zooplankton densities were not linked to variations in river flow, but 
salinity regimes regulated species composition and seasonal distribution. 

A three-and-a-half-year study (17) of the larger zooplankters in the same region (mouth of the San 
Jacinto River and southern Trinity Bay) identified 94 taxa dominated by crustaceans and fishes. Crab 
larvae, tentatively identified as Rhithropanopeus harrisii, were the most abundant group followed 
by other crustaceans such as Petrolisthes armatus, Pinnixa sp., Palaemonetes spp. and Callinectes 
spp., and by the fishes Brevoortia patronus and Anchoa mitchilli. Two broad seasonal groups were 
detected relating to abundance of organisms, with a "warm" season characterized by many larval 
crustaceans and few fishes and a "cool" season where the reverse trend was found. 

A 16-month study of the zooplankton of Christmas Bay (18) indicated that this high salinity 
embayment hosted a permanent zooplankton assemblage of three species (Mnemiopsis mccradyi, 
a ctenophore, and Acartia tonsa and Oithoina colcarva, copepods) apparently unaffected by 
temperature and salinity fluctuations. Other taxa such as larval crustaceans, other copepods, and the 
ctenophore Beroe ovata exhibited summer peaks in abundance. 

No zooplankton studies have been conducted in West Bay or East Bay. 

Benthos—Six benthic macroinvertebrate assemblages occur in the Galveston Bay complex, 
including open bay center, oyster reef, grassflat, bay margin, inlet-influenced and river-influenced 
assemblages (Table 2.4). The river-influenced assemblage covers the greatest area, including all of 
Trinity Bay, upper Galveston Bay, and part of East Bay. Oyster reef assemblages occur primarily in 
central Galveston Bay and divide Galveston Bay into upper and lower sections. Lower Galveston Bay 
contains primarily inlet-influenced and open bay center assemblages. The bay margin assemblage 
occurs on thebay side of Bolivar Peninsula and near Texas City. All six assemblages are found in West 
Bay. 


28 


The river-influenced assemblage contains a small group of common bay species, including the 
bivalve Mulinia lateralis, the polychaetes Capitella capita ta, Streblospio benedictiand Mediomas- 
tus spp., and brackish-water mollusks such as Macoma mitchelli, Texadina sphinctostoma and 
Rangia flexuosa. These species occur in parts of estuaries where salinities vary from fresh to brackish 
over long periods of time. Average salinities in Trinity Bay range from less than 5 ppt to about 10 ppt 
(15). However, over relatively short periods of time, the river-influenced assemblage is subjected to 
greater natural salinity fluctuations (0-33 ppt) than are other bay assemblages. 

In contrast to the river-influenced assemblage, the inlet-influenced assemblage contains the 
highest number of species, partly because of more stable salinities. This assemblage, composed 
primarily of mollusks, contains some species that are restricted to the area of Galveston and East Bays 
near Bolivar Roads and Rollover Pass and to West Bay near San Luis Pass. Common species include 
mollusks such as Mulinia lateralis, Lyonsia hyalina, Mysella planulata,Turbonilla sp., Acteocina 
canaliculata and Nassarius acutus and polychaetes such as Owenia fusiformis, Paraprionospio 
pinnata, Clymenella torquata and Mediomastus californiensis. 

The oyster reef assemblage is found primarily on or near reefs and is dominated by the American 
oyster Crassostrea virginica and the mollusks Ischadium recurvum, Brachidontes exustus and 
Mulinia lateralis. The common polychaetes Mediomastus californiensis and Streblospio 
benedicti are also abundant. 

The bay margin assemblage is limited to shallow, sandy stations in East and West Bays and lower 
Galveston Bay. Most stations are less than 2 km from shore and less than 1 meter deep. Crustaceans 
such as Ampelisca spp., Cerapus tubularis and Oxyurostylis salinoi are more abundant in the bay 
margin assemblage than in any other assemblage except the grassflat assemblage. 

Crustaceans are dominant in the grassflat assemblage and include such species as Ampelisca 
abdita, Acanthohaustorius sp. and Cymadusa compta. Bivalves such as Amygdalum papyrium, 
Lyonsia hyalina and Laevicardium mortoni and polychaetes such as Aricidea fragilis and Scol- 
oplos fragilis are common. Grassflats are of limited distribution in the Galveston Bay system and 
occur principally in patches along the margin of the Trinity River delta and Christmas Bay. 

The open bay center assemblage occurs in lower Galveston Bay and East and West Bays in muddy 
sediments and in relatively deep water. Polychaetes are the predominant group and are character¬ 
ized by Paraprionospio pinnata, Parandalia fauveli and Podarkeopsis levifuscina. 

A 12-month study of the benthos of Trinity Bay (1) indicated that polychaetes were the most 
speciose group collected (35 species), followed by crustaceans (18 species), mollusks (14 species), and 
bryozoans, rhynchocoels and chordates (5 species). Seventy-four percent of all individuals collected 
were polychaetes, primarily Mediomastus californiensis and other capitellids. Other abundant 
species were the mollusks Macoma sp., Amnicola sp. and Texadina sphinctostoma. Densities of 
benthic organisms exhibited spring and late summer peaks. 

Macroinvertebrates—These mobile and sessile species are rarely encountered using the plank¬ 
ton or benthic sampling methods involved in prior sections except as larval or early juvenile forms. 
No synoptic surveys of macroinvertebrates in the Galveston Bay system (other than oysters, 
Crassostrea virginica) have been conducted. The public oyster reefs within the estuary have been 
described (19, 20). The reefs are typically long and narrow, are oriented perpendicular to water 
currents, and are densest in the mid-bay region and across the mouth of East Bay. Settlement of spat 
(free-swimming larvae) generally occurs during April to November, primarily in the summer 
months. Oysters reach market size in 13 to 18 months. The distribution of oyster reefs depends on the 
interactions of temperature, salinity, predation and disease (19). High salinities allow an increased 
predation by oyster drills (Thais haemastoma) and increased infection by Perkinsus marinus 
("dermo"). Extensive periods of low salinity can also kill oysters, so most of the viable reefs are 
located in areas characterized by 10 to 20 ppt mean annual salinity. Since 1975, the areal distribution 
of oyster reefs has been stable. 

Although not well documented, there are numerous species of mobile macroinvertebrates in the 
estuary (13,21-24) (Table 2.5). All of these species were collected in western West Bay (but are found 
elsewhere) and many of these species are probably limited to submerged vegetation or oyster reef 
habitats, rarely caught elsewhere. In shallow, fringing habitats Palaemonetes spp. (grass shrimp) are 
most common and reach maximum abundance in March through July. Macrobrachium ohione 


29 


Table. 2.4. Characteristic Species in Macroinvertebrate Assemblages (15). 

Galveston-Trinitv-East Bays 


River-Influenced 

Bivalves 

Mulinia lateralis 
Macoma mitchelli 
Rangia flexuosa 
Gastropods 

Texadina sphinctostoma 
Vioscalba louisianae 
Texadina barretti 
Polychaetes 

Parandalia fauveli 
Streblospio benedicti 
Capitella capitata 
Mediomastus califomiensis 
Polydora ligni 
Crustaceans 

Corophium louisianum 

Inlet-Influenced 

Bivalves 

Mulinia lateralis 
Lyonsia hyalina floridana 
Tellina texana 
Gastropods 

Turbonilla cf. T. interrupta 
Nassarius acutus 
Polychaetes 

Owenia fusiformis 
Apoprionospio pygmaea 
Onuphis eremita oculata 

Bay Margin 

Bivalves 

Amygdalum papyrium 
Polychaetes 

Streblospio benedicti 
Paraprionospio pinnata 


Tharyx marioni 
Owenia fusiformis 
Crustaceans 

Oxyurostylis salinoi 
Monoculodes nyei 
Cerapus tubularis 
Hargeria rapax 

Open Bay Center 

Bivalves 

Mulinia lateralis 
Polychaetes 

Paraprionospio pinnata 
Pseudeurythoe ambigua 
Parandalia fauveli 
Sigambra spp. 

Crustaceans 

Acetes americanus 

Oyster Reef 

Gastropods 

Boonea impressa 
Texadina sphinctostoma 
Bivalves 

Crassostrea virginica 
Ischadium recurvum 
Brachidontes exustus 
Mulinia lateralis 
Polychaetes 
Nereis succinea 
Polydora ligni 
Mediomastus califomiensis 
Streblospio benedicti 
Parandalia fauveli 
Crustaceans 
Melita nitida 
Rhithropanopeus harrisii 
Cassidinidea lunifrons 


30 











West Bflv (in cluding Chocolate, Christmas and Bastrop Bays) 


Grassflat 

Bivalves 

Amygdalum papyrium 
Laevicardium mortoni 
Polychaetes 
Chone duneri 
Nereis succinea 
Streblospio benedicti 
Crustaceans 

Ampelisca abdita 
Edotea montosa 
Cerapus tubularis 
Listriella sp. 

Qy s t erRee f 

Bivalves 

Crassostrea virginica 
Ischadium recurvum 
Polychaetes 

Nereis succinea 
Crustaceans 

Grandidierella bonnieroides 
Oxyurostylis salinoi 
Rhithropanopeus harrisii 

River-Influenced 

Gastropods 

Texadina barretti 
Bivalves 

Macoma mitchelli 
Mulinia lateralis 
Polychaetes 

Parandalia fauveli 
Scoloplos fragilis 
Paraprionospio pinnata 
Glycinde solitaria 

Open Bay Center 

Bivalves 

Mulinia lateralis 


Mysella planulata 
Lyonsia hyalina floridana 

Polychaetes 

Paraprionospio pinnata 
Podarkeopsis levifuscina 
Cossura delta 

Mediomastus californiensis 
Melinna maculata 

inlet-influenced 

Gastropods 

Turbonilla cf. T. interrupta 
Acteocina canaliculata 
Bivalves 

Mulinia lateralis 
Periploma margaritaceum 
Mysella planulata 
Lyonsia hyalina floridana 
Polychaetes 

Paraprionospio pinnata 
Clymenella torquata 
Owenia fusiformis 
Mediomastus californiensis 
Crustaceans 

Ampelisca brevisimulata 
Bay Marg in 

Gastropods 

Acteocina canaliculata 
Acteon punctostriatus 
Bivalves 

Mulinia lateralis 
Ensis minor 

Lyonsia hyalina floridana 
Polychaetes 

Mediomastus californiensis 
Crustaceans 

Ampelisca abdita 
Ampelisca brevisimulata 
Oxyurostylis salinoi 


31 











Table 2.5. Macrocrustaceans Collected in Trawl Surveys of the Galveston Bay System (13, 
21-23). 

Stomatopods 

Crabs 

Squilla empusa 

Petrolisthes armatus 


Clibanarius vittatus 

Shrimp 

Pagurus longicarpus 

Penaeus setiferus 

Pagurus pollicaris 

Penaeus aztecus 

Ovalipes stephensoni 

Penaeus duorarum 

Callinectes sapidus 

Trachypenaeus similis 

Callinectes similis 

Xiphopenaeus kroyeri 

Menippe mercenaria 

Alpheus heterochaelis 

Rhithropanopeus harrisii 

Palaemonetes pugio 

Hexapanopeus angustifrons 

Palaemonetes vulgaris 

Neopanope texana 

Palaemonetes intermedius 

Eurypanopeus depressus 

Macrobrachium ohione 

Panopeus herbstii 

Periclimenes longicaudatus 

Pachygrapsus transversus 

Hippolyte zostericola 

Uca spp. 

Tozeuma carolinense 

Libinia dubia 


Heterocrypta granulata 


Table 2.6. Comparison of the Most Numerous Fishes Collected During a Two-Year Period 
in Various Galveston Bay Habitats (Rank Order) (27). 

Channels 

Open Bay 

Stellifer lanceolatus 

Micropogonias undulatus 

Micropogonias undulatus 

Anchoa mitchilli 

Symphurus plagiusa 

Cynoscion arenarius 

Anchoa mitchilli 

Stellifer lanceolatus 

Polydactylus octonemus 

Arius felis 

Arius felis 

Sphoeroides parvus 

Menticirrhus americanus 

Citharichthys spilopterus 

Brevoortia patronus 

Leiostomus xanthurus 

Citharichthys spilopterus 

Symphurus plagiusa 

Leiostomus xanthurus 

Polydactylus octonemus 

Nearshore Flats 

Peripheral Lagoons and Bayous 

Micropogonias undulatus 

Micropogonias undulatus 

Anchoa mitchilli 

Anchoa mitchilli 

Leiostomus xanthurus 

Leiostomus xanthurus 

Arius felis 

Cynoscion arenarius 

Sphoeroides parvus 

Mugil cephalus 

Brevoortia patronus 

Citharichthys spilopterus 

Cynoscion arenarius 

Brevoortia patronus 

Citharichthys spilopterus 

Arius felis 

Menticirrhus americanus 

Symphurus plagiusa 

Stellifer lanceolatus 

Sphoeroides parvus 


32 












(river shrimp) is found in low salinity areas during April and May. Postlarval Penaeus aztecus 
(brown shrimp) enter the estuary in February through April, move into shallow nurseries, and then 
reappear in large numbers in open bay waters during March through July. Penaeus setiferus (white 
shrimp) postlarvae begin entering the estuary in April and juveniles become most numerous in open 
waters during July through November. A small population of Penaeus duorarum (pink shrimp) 
enters as larvae to shallow estuarine nurseries in the fall and juveniles are recaptured in March 
through May in open bay waters. Callinectes sapidus (blue crab) is most susceptible to sampling gear 
in October through April but may recruit almost all year. One species not included in Table 2.5 but 
quite important to the system is Lolliguncula brevis (brief squid). It is a summer inhabitant of higher 
salinity waters (9) and may be an important determinant of community composition as a predator 
(25). 

Vertebrates 

This section encompasses fishes, birds, amphibians, reptiles and mammals, but only fishes have 
been the object of synoptic surveys. 

Fishes—A comprehensive list of the ichthyofauna of the Galveston Bay system encompassed 66 
families, 122 genera and 162 species (26). Freshwater fishes (9 families, 19 species) rarely found in the 
bay were included. Results of a two-year, synoptic trawl survey (27) indicated that, of 96 species 
recorded, six species accounted for 91 percent of the total number of fishes collected: Micropogonias 
undulatus (Atlantic croaker, 51 percent); Anchoa mitchilli (bay anchovy, 22 percent); Stellifer 
lanceolatus (star drum, 8 percent); Leiostomus xanthurus (spot, 4 percent); Cynoscion arenarius 
(sand seatrout, 3 percent); and Arius felis (hardhead catfish, 3 percent). These six species plus Mugil 
cephalus (striped mullet) were responsible for 74 percent of the biomass collected, dominated by 
Micropogonias (37 percent of the weight) over all others (<10 percent each). In general, the same 
small group of 13 species dominated catches in various bay habitats (Table 2.6). The total fish fauna 
was most numerous in April and May (dominated by Micropogonias) and least dense in December 
and January (dominated by Anchoa). Biomass peaks generally occurred May through August 
(Micropogonias, Stellifer), while the biomass of a mixed assemblage was lowest in November. 
Although no surveys have addressed West Bay proper, surveys of Chocolate Bayou (24) and 
Christmas Bay (13) revealed 72 and 83 species of fishes, respectively, with similar dominant species. 

Larval and postlarval fishes often numerically dominate zooplankton collections. The same 
species that later comprise the bulk of the trawl catches are usually the most abundant as plankters 
(17,18, 28). 

Birds—Although no comprehensive study of the avifauna of the Galveston Bay system has been 
conducted, observers and checklists have recorded 139 bird species associated with wetlands and 
bay habitats (29,30). This group of species accounts for 25 percent of the 565 bird species recorded 
for Texas (31). Further, these wetland-related forms do not include the large number of terrestrial 
resident or migratory birds. Three large groups of birds have a significant representation in the 
Galveston Bay system—waterfowl, shorebirds and colonial nesting waterbirds. 

Waterfowl are censused each January during the Mid-winter Waterfowl Survey, a cooperative 
effort between the Texas Parks and Wildlife Department and the U.S. Fish and Wildlife Service. These 
surveys have shown that 60 percent of Texas' wintering waterfowl are found on the upper Texas 
coast, including large populations of Chen caerulescens (snow goose), associated with rice-growing 
regions of the coastal prairies (32). Aerial surveys of the Galveston Bay system for the years 1978 and 
1984 through 1987 have recorded an average of 11,500 waterfowl annually. The five most common 
species observed during these surveys were Anas crecca (green-winged teal), Aythya collaris (ring¬ 
necked duck), Aythya affinis (lesser scaup), Mergus serrator (red-breasted merganser), and Oxyura 
jamaicensis (ruddy duck). Although a total of 32 species of waterfowl has been observed in the bay 
system (Table 2.7), only Dendrocygna bicolor (fulvous whistling duck), Anas fulvigula (mottled 
duck), Aix sponsa (wood duck), and Anas discors (blue-winged teal) are regular breeders in the area. 
The remaining species of waterfowl use the estuary during migration or while overwintering. 

The Galveston Bay system has been identified by the Western Hemisphere Shorebird Reserve 
Network as a regionally significant reserve site (34), denoting support of >5 percent of all mid¬ 
continental shorebird populations during migration. Large populations of migrating or overwinter- 


33 



Table 2.7. Waterfowl Observed in the Galveston Bay System (32, 33). 

Common Name 

Scientific Name 

Common Name 

Scientific Name 

Fulvous whistling 

Dendrocygna 

American wigeon 

Anas americana 

duck 

bicolor 

Canvasback 

Aythya valisineria 

Black-bellied whistling Dendrocygna 

Redhead 

Aythya americana 

duck 

autumnal is 

Ring-necked duck 

Aythya collaris 

Greater white-fronted 

Anser albifrons 

Greater scaup 

Aythya marila 

goose 


Lesser scaup 

Aythya affinis 

Snow goose 

Chen caerulescens 

Old squaw 

Clangula hyemalis 

Ross' goose 

Chen rossii 

Black scoter 

Melanitta nigra 

Canada goose 

Branta canadensis 

Surf scoter 

Melanitta 

Wood duck 

Aix sponsa 


perspicillata 

Green-winged teal 

Anas crecca 

White-winged scoter 

Melanitta fusca 

Mottled duck 

Anas fulvigula 

Common goldeneye 

Bucephala clangula 

Mallard 

Anas platyrhynchos 

Bufflehead 

Bucephala albeola 

Northern pintail 

Anas acuta 

Hooded merganser 

Lophodytes 

Blue-winged teal 

Anas discors 


cucullatus 

Cinnamon teal 

Anas cyanoptera 

Red-breasted merganser Mergus serrator 

Northern shoveler 

Anas dypeata 

Ruddy duck 

Oxyura jamaicensis 

Gadwall 

Anas strepera 

Masked duck 

Oxyura dominica 


Table 2.8. Shorebirds Recorded for the Galveston Bay System (33, 34). 


Common Na m e 
Black-bellied plover 
Lesser golden-plover 
Snowy plover 

Wilson's plover 
Semipalmated plover 

Piping plover 
Killdeer 

American oyster- 
catcher 

Black-necked stilt 

American avocet 

Greater yellowlegs 
Lesser yellowlegs 
Solitary sandpiper 
Willet 

Spotted sandpiper 
Upland sandpiper 

Eskimo curlew 
Whimbrel 


Sc ientific Name 
Pluvialis squatarola 
Pluvialis dominica 
Charadrius 
alexandrinus 
Charadrius wilsonia 
Charadrius 
semipalmatus 
Charadrius melodus 
Charadrius 
vociferus 
Haematopus 
palliatus 
Himantopus 
mexicanus 
Recurvirostra 
americana 
Tringa melanoleuca 
Tringa flavipes 
Tringa solitaria 
Catoptrophorus 
semipalmatus 
Actitis macularia 
Bartramia 
longicauda 
Numenius borealis 
Numenius 
phaeopus 


Common Name 
Long-billed curlew 

Marbled godwit 
Hudsonian godwit 
Ruddy tumstone 
Red knot 
Sanderling 


Sc ie ntif i c Name 

Numenius 
americanus 
Limosa fedoa 
Limosa haemastica 
Arenaria interpres 
Calidris canutus 
Calidris alba 


Semipalmatedsandpiper Calidris pusilla 
Western sandpiper Calidris mauri 

Least sandpiper Calidris minutilla 

White-rumped sandpiper Calidris fuscicollis 


Baird's sandpiper 
Pectoral sandpiper 
Dunlin 

Stilt sandpiper 

Buff-breasted sandpiper 

Short-billed dowitcher 

Long-billed dowitcher 

Common snipe 
American woodcock 
Wilson's phalarope 
Red-necked phalarope 
Red phalarope 


Calidris bairdii 
Calidris melanotos 
Calidris alpina 
Calidris 
himantopus 
Tryngitis 
subruficollis 
Limnodromus 
griseus 
Limnodromus 
scolopaceus 
Gallinago gallinago 
Scolopax minor 
Phalaropus tricolor 
Phalaropus lobatus 
Phalaropus 
fulicaria 


34 


















SEASONAL ABUNDANCE 


J FMRMJ J RSOND 

I I 1 I I I I I I I I I 


PHYTOPLHNKTON 


ZOOPLANKTON ° 


BENTHOS 

COLONIAL 
NESTING BIRDS 

SHORE BIRDS 
WATERFOWL 

LOW i n i n 


MEDIUM 


HIGH 



Figure 2.1. Seasonality of the components of the benthic food iveb in relation to the abundance of Galveston Bay avifauna 
(1,17,33,34,35,36,64). 


ing shorebirds utilize intertidal flats on Bolivar Peninsula and on the east and west ends of Galveston 
Island. Of the 35 species of shorebirds reported for Galveston Bay (Table 2.8), the most common forms 
are Pluvialis squatarola (black-bellied plover), Recurvirostra americana (American avocet), Ca- 
toptrophorus semipalmatus (willet), Calidris alba (sanderling), Calidris mauri (western 
sandpiper), Calidris alpina (dunlin), and Limnodromus spp. (dowitchers) (64). Peaks in shorebird 
utilization of Galveston Bay occur during the winter months through spring migration (December 
through May). Chronology of migration and intertidal flat use may be tied to macrobenthic prey 
phenology (Figure 2.1). Six species of shorebirds are known to nest in the bay complex: Charadrius 
wilsonia (Wilson's plover), Charadrius vociferus (killdeer), Haematopus palliatus (American 
oystercatcher), Himantopus mexicanus (black-necked stilt), willet and American avocet. 

Surveys of colonial nesting waterbirds in the Galveston Bay system have been conducted since 
1967 (33,35). During the period 1973 through 1987 (Figure 2.2), numbers of pairs of colonial nesting 
waterbirds varied from lows of approximately 39,000 in 1978 and 1985 to a high of 71,700 in 1982 with 
a mean of 52,136 (33). Active colony numbers have increased from 20 in 1973 to 42 in 1987. Colony 
sites include gravel and shell bars, Spartina alterniflora marshes, cypress stands, dredged material 
islands, and industrial and developed locations. Twenty-two species of colonial nesting waterbirds 
have been reported as nesting during the 21 years of surveys (Table 2.9). The three most common 
species during the 1986 nesting season were Larus atricilla (laughing gull). Sterna maxima (royal 
tern) and Bubulcus ibis (cattle egret) (36). 

Birds that have been identified as threatened or endangered by the U.S. Fish and Wildlife Service 
(33) include Pelecanus occidentalis (brown pelican), Charadrius melodus (piping plover), Nume- 
nius borealis (eskimo curlew). Sterna antillarum (interior least tern), Haliaeetus leucocephalus 
(bald eagle), Falco peregrinus (peregrine falcon), and Mycteria americana (wood stork). 

Amphibians and Reptiles—Ninety-two species of amphibians and reptiles have been reported 
for the four counties surrounding Galveston Bay (37). Mueller (38) described only 15 species of 
amphibians and reptiles from nontidal wetlands on Galveston Island, however. The American 


35 






















































































































































































Table 2.9. Colonial Nesting Waterbirds of the Galveston Bay System (36). 

Common Name 

Scientific Name 

Common Name 

Scientific Name 

Olivaceous cormorant 

Phalacrocorax 

White ibis 

Eudocimus albus 


olivaceus 

White-faced ibis 

Plegadis chihi 

Anhinga 

Anhinga anhinga 

Roseate spoonbill 

Ajaia ajaja 

Great blue heron 

Ardea herodias 

Laughing gull 

Larus atricilla 

Great egret 

Casmerodias albus 

Gull-billed tern 

Sterna nilotica 

Snowy egret 

Egretta thula 

Caspian tern 

Sterna caspia 

Little blue heron 

Egretta caerulea 

Royal tern 

Sterna maxima 

Tricolored heron 

Egretta tricolor 

Sandwich tern 

Sterna sandvicensis 

Reddish egret 

Egretta rufescens 

Forster's tern 

Sterna forsteri 

Cattle egret 

Bubulcus ibis 

Least tern 

Sterna antillarum 

Black-crowned 

night-heron 

Yellow-crowned 

night-heron 

Nycticorax 

nycticorax 

Nycticorax violaceus 

Black skimmer 

Rynchops niger 


Table 2.10. Game and Furbearing Mammals of the Four Counties Surrounding Galveston 
Bay (41,42). 


Common Name 

White-tailed deer 

Virginia opossum 

Beaver 

Muskrat 

Nutria 

Raccoon 

Ringtail 

Coyote 


Scientific Name 

Odocoileus 
virginianus 
Didelphis 
virginiana 
Castor canadensis 
Ondatra zibethicus 
Myocaster coypus 
Procyon lotor 
Bassariscus astutus 
Canis latrans 


Common Name 

Red fox 
Gray fox 

Long-tailed weasel 
Mink 

Eastern spotted skunk 
Striped skunk 
River otter 
Bobcat 


Scientific Name 

Vulpes vulpes 
Urocyon 

cinereoargenteus 
Mustela frenata 
Mustela vison 
Spilogale putorius 
Mephitis mephitis 
Lutra canadensis 
Felis rufus 


36 
















COLONIAL NESTING BIRDS 

80 


22 SPECIES 



NESTING 
PR IRS 
C1000s) 


YERR 


Figure 2.2. Abundance of colonial nesting birds during 1973-1987 (33,35). 


nCTIVE 

COLONIES 


alligator (Alligator mississippiensis) has recently become a harvestable animal under state statutes 
(39). During 1984-1986, a total of 655 alligators were harvested from the counties surrounding the 
estuary, with 384 (59 percent) taken in freshwater marshes of Chambers County. 

Reptiles that frequent the system and have been identified as threatened or endangered by the 
U.S. Fish and Wildlife Service (33) include: Dermochelys coriacea (leatherback sea turtle), Lepido- 
chelys kempi (Kemp's ridley sea turtle), Caretta caretta (loggerhead sea turtle) and Chelonia mydas 
(green sea turtle). Sea turtles were once an important component of the bay system, so much so that 
there was a commercial sea turtle fishery in Galveston Bay during the 1890's (40). 

Mammals—Schmidly (41, 42) documents 54 species of mammals for the counties surrounding 
Galveston Bay. Of these, 15 are furbearers and one is a game species (Table 2.10). The mammals most 
dependent upon wetlands environments include Sylvilagus aquaticus (swamp rabbit), Sciurus 
carolinensis (gray squirrel). Castor canadensis (beaver). Ondatra zibethicus (muskrat), Rattus 
rattus (roof rat), Oryzomys palustris (northern rice rat), Myocastor coypus (nutria), Procyon lotor 
(raccoon), Mustela vison (mink), Lutra canadensis (river otter), and Tursiops truncatus (bot¬ 
tlenosed dolphin). 


Dynamics and Interactions 

Some of the relationships of organisms to their physical environments were considered previ¬ 
ously, but the interactions of groups of organisms with extrinsic factors such as temperature, salinity, 
substrate and habitat availability need to be emphasized. This section will generally follow the 
trophic structure of the estuary. 

Primary Productivity 

The relative contribution of each floral component to total system primary production has been 


37 


















































































































Table 2.11. Primary Productivity in the Galveston Bay System (Data Sources in Parentheses). 



Average 

Estimated 


Estimated 


Primary 

Areal 

Annual 


Productivity 

Coverage 

Production 

Flora 

(g dry/m 2 /yr) 

(km 2 ) 

(metric tons) 

Phytoplankton (44,45,47) 

350 

1,425 

498,750 

Benthic microflora (44,47) 

500 

1,425 

712,500 

Submerged vegetation (1,15,48) 

2,600 

1 

2,600 

Freshwater marsh (1,12) 

820 

40 

32,800 

Salt-Brackish Marsh (12,43) 

1,100 

370 

407,000 

Woodlands/swamps (12,47) 

700 

500 

350,000 


roughly estimated in Table 2.11. Phytoplankton, benthic microflora, salt and brackish marshes, and 
woodlands and swamps each contribute roughly the same order of magnitude of organic materials 
to annual production. Fresh marshes produce an order of magnitude less, while seagrasses contrib¬ 
ute two orders of magnitude less production than the four main components. Some of the assump¬ 
tions made in constructing Table 2.11 need testing, such as productivity of phytoplankton and 
benthic microflora within Galveston Bay and presumption that such productivity occurs under the 
total bay surface of 1,425 km 2 (550 mi 2 ). Within the various habitats, the variation in productivity can 
be dramatic. For example, in the fresh marsh Sagittaria graminea produces 215 g dry/m 2 /year while 
Phragmites australis produces 2,984 g dry/m 2 /year (1), and in the salt marsh Batis maritima 
produces 425 g dry/m 2 /year while Spartina spp. produce 1,100 g dry/m 2 /year (43). The most 
productive component, the seagrasses, are the least abundant in this estuary. 

Most of the plant production is separated in space and time from the consumer community. In 
fact, some of that production may never reach the consumers due to inundated regimes and tissue 
storage. It has been estimated that woodlands, swamps and freshwater marshes export only 8 to 10 
percent of the annual aboveground production whereas the frequently inundation low salt marshes 
may export 30 to 45 percent annually (1,47). The low nutritional quality, refractory nature of much 
of the biomass, and resistance to direct grazing all increase from phytoplankton and algae through 
submerged aquatic vegetation to emergent vascular plants of the salt marsh and woodlands. Thus, 
the primary consumption of most of the plant biomass is only available along the detritus pathway. 
Although many organisms play major roles in breaking down this refractory material, they rarely 
directly assimilate the organic plant matter and, instead, utilize the surface microbial decomposers 
(47). 

Primary Consumption 

Less than 10 percent of emergent vegetation of these wetlands is consumed directly, and most of 
the grazers are insects (47). Ondatra zibethicus (muskrat) and Myocastor coypus (nutria) are other 
direct consumers. Submerged vegetation may be directly consumed by a small number of aquatic 
organisms (snails, fishes such as Lagodon rhomboides [pinfish]) as well as certain species of ducks. 
Phytoplankton are directly grazed by many zooplankters and planktivorous fishes, while benthic 
algae and epiphytes are utilized by snails, fiddler crabs and other organisms (47). The vast majority 
of primary consumers in the system are detritivores, species that directly or indirectly consume 
detrital particles and, lacking the necessary digestive enzymes, in reality utilize only the surface 
bacteria and fungi. This group includes many benthic organisms (bivalves, gastropods, crustaceans) 
and bottom feeding fishes and macroinvertebrates (47). 

The available evidence suggests that the phytoplankton-based branch of the food web may not 
be as important to the Galveston Bay system as is the emergent marsh-detritus branch, even though 
annual primary production may be similar for both groups. First, average phytoplankton densities 


38 





are on the low end of the scale for Texas estuaries (1), which are, in turn, on the low end of the range 
of estuarine production in general (44). Second, zooplankton densities (the main consumers of 
phytoplankton) are also on the low end of the ranges seen in other Texas estuaries (1). Third, salt 
marsh productivity is higher in Texas than in most other Atlantic and Gulf coast states (63). Finally, 
the macrobenthic and fish faunas are omnivores or carnivores except in their earliest larval stages 
(47). 

Habitat Utilization 

Vegetated habitats serve other functions than providing direct or indirect sources of food. Aside 
from these, wetlands function as natural water treatment plants for nutrients and wastes, provide 
aesthetic value, control biogeochemical cycles of elements such as nitrogen and sulphur, buffer 
inlands from storms and reduce flooding, and provide useful products such as lumber. Perhaps the 
most significant functions of wetlands for estuarine organisms are provision of nursery areas for 
feeding, refuge and substrate utilization by other organisms. In a Spartina altemiflora marsh, 
densities of crustaceans such as Palaemonetes pugio, Callinectes sapidus and Penaeus aztecus and 
fishes such as Lagodon rhomboides, Fundulus spp., Sciaenops ocellatus and Cynoscion nebulosus 
were all significantly higher in flooded marsh areas than in adjacent non-vegetated waters (23,49). 
During most seasons, densities of juveniles of many commercially, recreationally and ecologically 
important fishes and crustaceans are higher in vegetated habitats such as salt marshes, fresh marshes 
and seagrasses around Galveston Bay than in adjacent open waters (Figure 2.3, from 50). There are 
indications that the vegetative structure provides refuge from predators and foods (such as epiphytic 
algae and high densities of infauna) not found in open waters (50-52). The connection between 
amounts of vegetated habitats and fisheries productivity in adjacent waters has been demonstrated 
worldwide. For example, landings of brown shrimp in nearshore Louisiana waters have been 
directly linked to the amount of salt marsh vegetation present (53). Thus, wetlands habitats are quite 
valuable in many aspects. 

Fisheries 

The Galveston Bay system supports a wide variety of species in its bay and nearshore commercial 
and recreational fisheries (Table 2.12). In 1986, commercial fisheries landed more than 10,000 metric 
tons of seafood with a dockside value exceeding $26 million for the top 10 species alone (Table 2.13). 
The commercial catches were dominated by invertebrates such as brown shrimp, pink shrimp and 
white shrimp (totaling 6.8 million kilograms), blue crabs (1.4 million kilograms) and oysters (1.6 
million kilograms, whole) (54). Southern and gulf flounders and Atlantic croaker were the dominant 
finfishes. The 1986 recreational fisheries landed in excess of 280 tons, primarily of sportfishes such 
as spotted seatrout, sand seatrout, southern and gulf flounders, Atlantic croaker and redfish (55). 

Since 1960, landings of penaeid shrimp, oysters and blue crabs have been relatively stable given 
some degree of annual fluctuation (Figure 2.4) (54, 56). Some abrupt changes have been due to 
regulatory actions such as closing of bays to oyster harvesting after heavy rainfall and pollutant 
loading. An apparent upward trend in shrimp landings is in part due to increasing inshore fishing 
effort but may also indicate increasing marsh access (discussed later). Fluctuations in finfish landings 
since 1975 (Figure 2.5) (54, 55) were primarily due to regulatory actions in the face of heavy 
commercial and recreational fishing pressure on spotted seatrout (Cynoscion nebulosus) and 
redfish (Sciaenops ocellatus) in the late 1970's. Commercial landings of spotted seatrout and redfish 
were banned, thus the decline seen around 1980. The commercial fishery is now increasing, with 
flounders the dominant species and mullets, Atlantic croaker, black drum and sheepshead next in 
importance. Recreational fishing, now controlled by size and bag limits on certain species, has 
stabilized and is led by landings of spotted seatrout followed by sand seatrout, redfish, flounders and 
Atlantic croaker. 

A synopsis of commercial and recreational fisheries (Figure 2.6) indicates that landings are 
generally highest in summer and fall months, with the exception of oysters that are a winter-spring 
harvest with public reefs closed during the warm months. The blue crab fishery reaches a maximum 
in early summer. The bait shrimp fishery is most productive in summer and fall, coincidently when 
both demand and supply are highest. The bay commercial shrimp fishery has two seasons separated 
by closures: a June and July fishery for brown shrimp (Penaeus aztecus) and an August through 


39 



SPRING SUMMER 


FALL 


SPRING SUMMER FALL 


NUMBER 
10 PER 
M 2 


SEAGRASS 
MARSH 
SAND 



NUMBER 


5 M 


PER 
2 


SEAGRASS 
MARSH 
SAND 


Figure 23. Habitat selection by penaeid shrimp (Penaeus spp.)and blue crabs (Callinectes sapidus) in various aquatic 
habitats of the Galveston Bay estuary (50). 


40 


























































































































































Table 2.12. List of Common and Scientific Names of Commercial and Recreational Finfish 
and Shellfish Caught or Landed in Texas (54, 55). 

Cammftn.Name 

Scientific Name 

Finfish 


African pompano 

Alectis alaiis 

Alligator gar 

Lepisosteus spatula 

Atlantic croaker 

Micropogonias undulatus 

Atlantic cutlassfish 

Trichiurus lepturus 

Atlantic moonfish 

Selene setapinnis 

Atlantic needlefish 

Strongylura marina 

Atlantic spadefish 

Chaetodipterus faber 

Atlantic stingray 

Dasyatis sabina 

Black drum 

Pogonias cromis 

Bluefish 

Pomatomus saltatrix 

Blue catfish 

Ictalurus furcatus 

Channel catfish 

Ictalurus punctatus 

Cobia 

Rachycentron canadum 

Codfish 

Family Gadidae 

Dolphin 

Coryphaena hippurus 

Flounder 


Gulf flounder 

Paralichthys albigutta 

Southern flounder 

Paralichthys lethostigma 

Florida pompano 

Trachinotus carolinus 

Freshwater drum 

Aplodinotus gruniens 

Gaff topsail catfish 

Bagre marinus 

Greater amberjack 

Seriola dumerilli 

Grouper 


Black grouper 

Mycteroperca bonaci 

Jewfish 

Epinephelus itajara 

Nassau grouper 

Epinephelus striatus 

Scamp 

Mycteroperca phenax 

Warsaw grouper 

Epinephelus nigritus 

Yellowedge grouper 

Epinephelus flavolimbatus 

Yellowfin grouper 

Mycteroperca venenosa 

Yellowmouth grouper 

Mycteroperca interstitialis 

Gulf butterfish 

Peprilus burti 

Hardhead catfish 

Arius felis 

Kingfish 


Gulf kingfish 

Menticirrhus littoralis 

Southern kingfish 

Menticirrhus americanus 

Ladyfish 

Elops saurus 

Largemouth bass 

Micropterus salmoides 

Little tunny 

Euthynnus alletteratus 

Mackerel 


King mackerel 

Scomberomorus cavalla 

Spanish mackerel 

Scomberomorus maculatus 

Menhaden 

Brevoortia patronus 

Mullet 


Striped mullet 

Mugil cephalus 

White mullet 

Mugil curema 

Ocellated flounder 

Ancylopsetta quadrocellata 

Permit 

Trachinotus falcatus 


41 






Table 2.12. (Continued) 


Common Name 

Scientific Name 

Pigfish 

Orthopristis chrysoptera 

Pinfish 

Lagodon rhomboides 

Red drum 

Sciaenops ocellatus 

Sea trout 

Sand sea trout 

Cynoscion arenarius 

Silver seatrout 

Cynoscion nothus 

Spotted seatrout 

Cynoscion nebulosus 

Shark 

Atlantic sharpnose 

Rhizoprionodon terraenovae 

Blacktip 

Carcharhinus limbatus 

Bull 

Carcharhinus leucas 

Great hammerhead 

Sphyrna mokarran 

Scalloped hammerhead 

Sphyma lewini 

Shortfin mako 

Isurus oxyrinchus 

Smooth dogfish 

Mustelis canis 

Sheepshead 

Archosargus probatocephalus 

Silver perch 

Bairdiella chrysoura 

Smallmouth buffalo 

Ictiobus bubalus 

Smooth puffer 

Lagocephalus laevigatus 

Snapper 

Lane snapper 

Lutjanus synagris 

Red snapper 

Lutjanus campechanus 

Vermilion snapper 

Rhomboplites aurorubens 

Southern stingray 

Dasyatis americanus 

Spot 

Leiostomus xanthurus 

Striped burrfish 

Chilomycterus schoepfi 

Swordfish 

Xiphias gladius 

Tilefish 

Lopholatilus chameleonticeps 

Triggerfish, gray 

Balistes capriscus 

Tripletail 

Lobotes surinamensis 

Tuna 

Blackfin tuna 

Thunnus atlanticus 

Bluefin tuna 

Thunnus thynnus 

Yellowfin tuna 

Thunnus albacares 

Wahoo 

Acanthocybium solanderi 

Shellfish 

Atlantic bay scallop 

Argopecten irradians 

Crab 

Blue crab 

Callinectes sapidus 

Stone crab 

Menippe mercenaria 

American oyster 

Crassostrea virginica 

Shrimp 

Brown shrimp 

Penaeus aztecus 

White shrimp 

Penaeus setiferus 

Pink shrimp 

Penaeus duorarum 

Rock shrimp 

Sicyonia brevirostris 

Royal red shrimp 

Hymenopenaeus robustus 

Seabob 

Xiphopenaeus kroyeri 

Squid 

Brief squid 

Lolliguncula brevis 

Lone-finned squid 

Loligo pealei 


42 






Table 2.13. Landings by Galveston Bay Fisheries During 1986, Including Bay and Nearshore 
Waters (NMFS Statistical Subarea 18). Landings (Kilograms, kg) and Ex-vessel 
Value ($) Are in Thousands. ? = Ex-vessel Value Not Available (54, 56). 


Commercial Recreational 



Kg 

$ 

Kg 

$ 

Flounder 

73 

157 

39 

52 

Atlantic croaker 

18 

9 

37 

11 

Spotted seatrout 

- 

- 

102 

? 

Sand seatrout 

- 

- 

57 

? 

Redfish 

- 

- 

43 

? 

Oysters 

1,610 

6,950 

? 

? 

Blue crabs 

1,375 

1,043 

? 

? 

Shrimp (3 species) 

6,820 

18,135 

? 

? 


METRIC TONS LANDED 



Figure 2.4. Annual landings (1960-1986) of blue crabs, oysters and three species ofpenaeid shrimp from Galveston Bay 
and nearshore waters (54,56). 


43 






























































































































METRIC TONS LANDED 



Figure 25. Annual landings (1975-1986) of commercial and recreational finfishes from Galveston Bay and nearshore 
waters (54,56). 

October fishery for white shrimp (P. setiferus). Recreational finfish fisheries are most productive in 
summer (spotted sea trout, redfish) and fall (flounder). Commercial finfish harvests are highest in the 
fall, concentrating on flounder, mullet and Atlantic croaker. 

Ecological Interactions and Problems 

The greatest problems involved in the maintenance of the Galveston Bay biota are related to 
human utilization of estuarine resources such as wetlands, fresh water and coastal habitats. Each of 
these areas presents its own unique interactions and prospects for various scenarios of the future 
status of the bay. 

Sea Level Rise and Wetlands Loss 

One of the critical problems facing the Galveston Bay estuary is apparent sea level rise (a 
combination of rapid, local subsidence of land due to groundwater and petroleum withdrawal (15) 
and slow, oceanic water rise from glacial melting) and associated wetlands loss. As pointed out in 
previous sections, many estuarine inhabitants depend on wetlands for food, refuge or living space. 
In 1979, the area containing the estuary's wetlands had elevations of 0 to 1.6 meters above mean sea 
level and encompassed some 740 square kilometers (Figure 2.7) (15). 

The result of the combined forces of subsidence and glacial melting has led to a moderate 
projection of a 1.0- to 1.6-meter sea level rise by the year 2100 (57). If a 1.6-meter rise were experienced, 
the new wetlands area (0- to 1.6-meter elevations) would decrease in size by more than 50 percent to 
360 square kilometers (Figure 2.8), assuming inland migration of the vegetation. The old 0- to 1.6- 
meter elevations would be converted to open bay water. However, this new wetlands area is 


44 



































































































MONTHLY LHNDINGS 


JFMRMJ J RSOND 

i i i i i i i i i i i 


OYSTERS 
BLOE CRRBS 

BRIT SHRIMP 

COMM. SHRIMP 

REC. FISH 
COMM. FISH 



LOW 


MEDIUM 


HIGH 



CLOSED [=□ 


Figure 2.6. Seasonal landings by commercial (comm.) and recreational (rec.) fisheries in Galveston Bay (54,56). 


precisely where houses, industry, bulkheads and other of man's accomplishments are now located. 
Thus, the actual wetlands area will be much less than 360 square kilometers. 

What does this signify for fisheries and for estuary-dependent species in general? As sea level 
rises and marsh retreat is impeded by civilization, the acreage of wetlands accessible to fishery 
organisms and contributing to their life cycles will decline, and shortly thereafter so will the fisheries 
that are currently harvested (58). In the meantime, marshes will be inundated for increasing amounts 
of time and thus will become "drowning" marshes on the way to extinction. This is a temporarily 
beneficial situation for the various fishes, invertebrates, birds, reptiles and mammals that utilize the 
marsh surface, since marsh utilization may be promoted by increases in (1) estuarine area, (2) 
duration of flooding and thus access, and (3) marsh-open water interface for materials exchanges. In 
other words, for an interim period greater marsh access could lead to greater system productivity 
(58). 

Galveston Bay itself may be too small to detect the results of apparent sea level rise, although as 
mentioned previously shrimp catches are increasing and may be due in part to increased marsh 
access. However, on a Gulf of Mexico basis, the increased access to marshes due to drowning has led 
to detectable increases in recruitment of at least three commercial species for which a long-time series 
of data is available — gulf menhaden, brown shrimp and white shrimp (Figure 2.9) (58). From 1960 
through 1985, catch statistics and population analyses have detected a 200 percent increase in the 
number of young gulf menhaden harvested and 50 percent increases in abundances of newly 
recruited shrimps. The effects of marsh disintegration are beginning to show up. 

Freshwater Inflow and Saltwater Intrusion 

Another problem facing the Galveston Bay biota is that of controlling fresh water and the 
associated change in salt water distribution. Two species of economic importance that are especially 
influenced by fresh water are oysters and white shrimp. 


45 

































































































































































Figure 2.7. Low elevation areas (0-1.6 meters, shaded) Figure 2.8. Low elevation areas (0-1/6 meters, shaded) 
where Galveston Bay wetlands werelocated in where future Galveston Bay wetlands could 

1979, barring development (15). exist, barring development, after a 1.6-meter 

rise in sea level by the year 2100 (15). 

Oyster survival and production are excellent indicators of the natural patterns of mixing of fresh 
and salt waters (19,20). Under ideal situations oysters survive and grow well at salinities of 10 to 35 
ppt. However, salinities of more than 20 ppt bring predators (such as oyster drills) and disease (such 
as "dermo") that decrease survival and production. Fresh water kills are also incurred if salinities 
drop below 10 ppt for extended periods or at the wrong time of year. The net result is the typical 
pattern of oyster reef formation primarily where waters are consistently 10 to 20 ppt. Major shifts in 
the seasonal timing or amounts of discharge from river systems could cause long-term changes in 
oyster reef distribution and production. 

To a constricted arm of the Galveston Bay system, such as West Bay, a freshet of unrestricted flow 
can be quite beneficial for oysters. West Bay had been a high salinity-low production bay until a July 
1979 tropical storm dropped 110 cm of rain in 24 hours (59). Salinities were dramatically lowered and, 
combined with subsequent high settlement of oyster spat, reported oyster harvest jumped from zero 
tol,225 metric tons in the November 1982 through April 1983 season and 907 metric tons the fol¬ 
lowing season (Figure 2.10) (60). Since then, salinities have increased and reported oyster harvest has 
tapered off. 

When fresh water inflow patterns are artificially altered, the results may not be so beneficial to 
white shrimp productivity. Sabine Lake is located between Galveston Bay and Lake Calcasieu, 
Louisiana. Dams were built on the Sabine and Neches Rivers in 1965-1966 that contained the natural 
peak river flows of January through May for later release in generating electricity in the normally low 
flow period of June through October (61). Portions of the surrounding marshes were also leveed off 
at the same time. These summer flood conditions negated recruitment of white shrimp to nursery 
areas by artificially lowering salinities to unacceptable levels. The Sabine Lake white shrimp fishery 
collapsed, while fisheries in Galveston Bay and Lake Calcasieu continue (Figure 2.11) (56). 


46 





















Figure 2.9. Increases in recruitment of menhaden, brown shrimp and white shrimp to U.S. Gulf of Mexico fisheries 
between 1960 and 1985 (58). 



47 














































































































































Figure 2.11. White shrimp production in Sabine Lake, Texas (1962-1986) before and after the Sabine and Neches Rivers 
were dammed in 1966 compared with landings in Galveston Bay and Lake Calcasieu, Louisiana (56). 


Habitat Alteration 

The linkage between abundance of (and access to) wetlands and system productivity has been 
discussed. Just where does Galveston Bay fall when habitat protection is mentioned? In 1979, the 
estuary was surrounded by approximately 715 square kilometers of wetlands (determined from 
maps in 15). Wetlands losses between surveys in 1956 and 1979, whether natural or due to human 
activities, have been severe (15). In the Marsh Point area of East Bay, subsidence and petroleum 
exploration canals led to a 26 percent loss of salt and brackish marsh to open water. Jones Bay, at the 
northeast end of West Bay, suffered a 37 percent loss of marsh area due to housing development and 
its location on the edge of one of the two major subsidence cones in the Houston area. At the mouth 
of the San Jacinto River, subsidence has caused a 42 percent reduction of fresh marshes and swamps. 
Sea grasses and other submerged vegetation, primarily found in West Bay but never very extensive, 
have declined precipitously by 95 percent on a baywide basis. Galveston Island itself has lost 37 
percent of its wetlands due to housing projects and industrialization (62). For the entire estuary, a net 
loss of 16 percent of the vegetated wetlands occurred during the period 1956 through 1979. A 
complete system inventory is needed to determine what has transpired in the last eight years, a 
period during which Houston experienced a rapid population growth. 

Conclusion 

Given all the above information, a distillation of the material leads to three important facts to 
remember concerning the health of the Galveston Bay biota: 


48 
































































































• There is a critical dependence of fish and wildlife on wetlands; 

• A continued decline in wetlands acreage is foreseen; and 

• The timing and amount of fresh water inflow are critical to the biota as we now know it. 

References 

1. Texas Department of Water Resources. 1981. Trinity-San Jacinto estuary: a study of the influence 
of freshwater inflows. TDWR Report LP-113, Austin, TX, 386 p. 

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3. Oppenheimer, C.H. and E.J.F. Wood. 1965. Quantitative aspects of the unicellular algal popula¬ 
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4. Dykstra, R.F., F.J. MacEntee, and H.C. Bold. 1975. Some edaphic algae of the Texas coast. Tex. J. 
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5. Zimmerman, R.J., National Marine Fisheries Service, Galveston, TX, unpublished data. 

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8. Pullen, E.J. 1962. An ecological survey of upper Galveston and Trinity Bays. Texas Game and Fish 
Comm., Mar. Fish. Proj. Rep., Project No. M-2-R-3. 5 p. 

9. Reid, G.K., Jr. 1955. A summer study of the biology and ecology of East Bay, Texas. I. 
Introduction, description of the area, some aspects of the fish community, the invertebrate 
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10. Johnson, R.B. 1966. The effects of engineering projects on the ecology of Jones Bay, p. 148-157. In 
Texas Parks Wildl. Dep., Coastal Fisheries Project Reports, Austin, TX. 

11. Johnson, R.B. 1966. The effects of engineering projects on Moses Lake, p. 159-168. In Texas Parks 
Wildl. Dep., Coastal Fisheries Project Reports, Austin, TX. 

12. Fisher, W.L., J.H. McGowen, L.F. Brown, Jr., and C.G. Groat. 1972. Environmental geologic atlas 
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Texas, Austin, TX, 91 p. 

13. McEachron, L.W., C.R. Shaw, and A.W. Moffett. 1977. A fishery survey of Christmas, Drum and 
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14. West, R.L. 1972. Inventory of aquatic vegetation. Texas Parks Wildl. Dep., Coastal Waterfowl 
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15. White, W.A., T.R. Calnan, R.A. Morton, R.S. Kimble, T. G. Littleton, J.H. McGowen, H.S. Nance, 
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geochemistry, benthic macroinvertebrates, and associated wetlands. Bureau of Economic Geol- 
ogy, Univ. of Texas, Austin, TX, 145 p. 

16. Lazarine, P. undated. Common wetland plants of southeast Texas. U.S. Army Corps of Engi¬ 
neers, Galveston District, Galveston, TX, 135 p. 

17. Holt, G.J.D. 1976. Community structure of macrozooplankton in Trinity and upper Galveston 
Bays, with special reference to the cooling water system of Cedar Bayou Electric Generating 
Station. Ph.D. Dissertation, Texas A&M University, College Station, TX, 96 p. 

18. Bagnall, R.A. 1976. Definition and persistence of an estuarine zooplankton assemblage. Ph.D. 
Dissertation, Univ. of Houston, Houston, TX, 137 p. 

19. Hofstetter, R.P. 1977. Trends in population levels of the American oyster Crassostrea virginica 
Gmelin on public reefs in Galveston Bay, Texas. Texas Parks and Wildl. Dep., Tech. Ser. No. 24, 
90 p. 

20. Hofstetter, R.P. 1983. Oyster population trends in Galveston Bay 1973-1978. Texas Parks and 
Wildl. Dep., Manag. Data Ser. No. 51.33 p. 


49 


21. Johnson, R.B., Jr. 1974. Ecological changes associated with the industrialization of Cedar Bayou 
and Trinity Bay, Texas. Texas Parks Wildl. Dep., Tech. Ser. No. 16, 79 p. 

22. Trent, L., E.J. Pullen and R. Proctor. 1976. Abundance of macrocrustaceans in a natural marsh 
altered by dredging, bulkheading and filling. Fishery Bull. (U.S.) 74:195-200. 

23. Zimmerman, R.J. and T.J. Minello. 1984. Densities of Penaeus aztecus, Penaeus setiferus, and 
other natant macrofauna in a Texas salt marsh. Estuaries 7(4A):421-433. 

24. Moffett, A.W. 1975. The hydrography and macro-biota of the Chocolate Bayou estuary, Brazoria 
County, Texas (1969-1971). Texas Parks Wildl. Dep., Tech. Ser. No. 14, 72 p. 

25. Hargis, V. A. and R.T. Hanlon. University of Texas Medical Branch, Marine Biomedical Institute, 
Galveston, TX, unpublished data. 

26. Parker, J.C. 1965. An annotated checklist of the fishes of the Galveston Bay system, Texas. Publ. 
Inst. Mar. Sci. Univ. Texas 10:201-220. 

27. Sheridan, P.F. 1983. Abundance and distribution of fishes in the Galveston Bay system, 1963- 
1964. Contrib. Mar. Sci. 26:143-163. 

28. Arnold, E.L., Jr., R.S. Wheeler, and K.N. Baxter. 1960. Observations on fishes and other biota of 
East Lagoon, Galveston Island. U.S. Fish Wildl. Serv., Spec. Sci. Rep. 344,30 p. 

29. Feltner, T.B. and A.N. Pettingell. 1980. A birder's checklist of the upper Texas coast, 6th edition. 
Ornithology Group, Houston Outdoor Nature Club, Houston, TX. 

30. Arnold, K.A. 1984. Checklist of the birds of Texas. Texas Ornithological Society, Austin, TX. 147 
P- 

31. Arnold, K. A., Department of Wildlife and Fisheries, Texas A&M University, College Station, TX, 
unpublished data. 

32. Texas Parks and Wildlife Department. 1986. Waterfowl harvest recommendations. Texas Parks 
Wildl. Dep., Job Performance Rep., Project No. W-106-R-12.122 p. 

33. Mueller, A.J., U.S. Fish and Wildlife Service, Houston, TX, unpublished data. 

34. Myers, J.P., R.I.G. Morrison, P.Z. Antas, B.A. Harrington, T.E. Lovejoy, M. Sallaberry, S.E. Senner, 
and A. Tarak. 1987. Conservation strategy for migrating species. Amer. Scientist 75:19-26. 

35. Blacklock, G.W., R.D. Slack, D.B. Blankinship, S. Kennedy, K.A. King, R.T. Paul, J. Smith, and R.C. 
Telfair, III. 1978. The Texas colonial waterfowl census, 1973-1976. Proc. 1978 Conf. Colonial 
Waterfowl Group, pp. 99-104. 

36. Texas Parks and Wildlife Department. 1987. Texas colonial waterbird census summary - 1986. 
Texas Parks Wildl. Dep. and Texas Colonial Waterbird Soc., Spec. Admin. Rep., Austin, TX. 

37. Dixon, J.R. 1987. Amphibians and reptiles of Texas. Texas A&M University Press, College 
Station, TX, 434 p. 

38. Mueller, A.J. 1985. Vertebrate use of nontidal wetlands on Galveston Island, Texas. Texas J. Sci. 
37:215-225. 

39. Johnson, L., C. Martin, and B. Thompson. 1987. Texas alligator survey, harvest, and nuisance 
summary, 1986. Texas Parks Wildl. Dep., Annual Rep., Austin, TX, 18 p. 

40. Doughty, R.W. 1984. Sea turtles in Texas: a forgotten commerce. Southwest. Historical Quart. 
88:43-70. 

41. Schmidly, D.J. 1983. Texas mammals east of the Balcones fault zone. Texas A&M University 
Press, College Station, TX, 400 p. 

42. Schmidly, D.J. 1984. The furbearers of Texas. Texas Parks Wildl. Dep., Bull. No. Ill, 55 p. 

43. Ward, G.H. and N.E. Armstrong. 1980. Matagorda Bay, Texas: its hydrography, ecology, and 
fishery resources. U.S. Fish Wildl. Serv., Biological Services Program, Washington, DC, FWS/ 
OBS-81/52. 230 p. 

44. Flint, R.W. 1984. Phytoplankton production in the Corpus Christi Bay estuary. Contrib. Mar. Sci. 
27:65-83. 

45. Corliss, J. and L. Trent. 1971. Comparison of phytoplankton production between natural and 
altered areas in West Bay, Texas. Fishery Bull. (U.S.) 69:829-832. 


50 


46. Lowe, G.C., Jr. and E.R. Cox. 1978. Species composition and seasonal periodicity of the marine 
benthic algae of Galveston Island, Texas. Contrib. Mar. Sci. 21:9-24. 

47. Gosselink, J.G., C.L. Cordes, and J.W. Parsons. 1979. An ecological characterization study of the 
Chenier Plain coastal ecosystem of Louisiana and Texas. Vols. I-III. U.S. Fish Wildl. Serv., Office 
of Biological Services, Washington, D.C., FWS/OBS-78/9-11. 

48. McRoy, C.P. and C. McMillan. 1977. Production ecology and physiology of seagrasses, p. 53-87. 
In C.P. McRoy and C. Helfferich (eds.), Seagrass Ecosystems. Marcel Dekker, Inc., New York. 

49. Zimmerman, R.J., T.J. Minello, and G. Zamora. 1984. Selection of vegetated habitat by Penaeus 
aztecus in a Galveston Bay salt marsh. Fishery Bull. (U.S.) 82:325-336. 

50. Zimmerman, R.J., National Marine Fisheries Service, Galveston, TX, unpublished data. 

51. Minello, T.J. and R.J. Zimmerman. 1983. Fish predation on juvenile brown shrimp, Penaeus 
aztecus Ives: the effect of simulated Spartina structure on predation rates. J. Exp. Mar. Biol. Ecol. 
72:211-231. 

52. Gleason, D.F. 1986. Utilization of salt marsh plants by postlarval brown shrimp: carbon 
assimilation rates and food preferences. Mar. Ecol. Prog. Ser. 31:151-158. 

53. Turner, R.E. 1977. Intertidal vegetation and commercial yields of penaeid shrimp. Trans. Amer. 
Fish. Soc. 106:411-416. 

54. Osbum, H.R., W.D. Quast, and C.L. Hamilton. 1987. Trends in Texas commercial fishery 
landings, 1977-1986. Texas Parks Wildl. Dep., Manage. Data Ser. No. 131.108 p. 

55. Osbum, H.R., and M.O. Ferguson. 1987. Trends in finfish landings by sport-boat fishermen in 
Texas marine waters. May 1974-May 1986. Texas Parks Wildl. Dep., Manage. Data Ser. No. 119. 
464 p. 

56. Baxter, K.N. and Hightower, M., National Marine Fisheries Service, Galveston, TX, unpublished 
data. 

57. Titus, J.G. 1986. The causes and effects of sea level rise, p. 219-248. In J.G. Titus (ed.). Effects of 
Changes in Stratospheric Ozone and Global Climate. Vol. I. Overview. U.S. Environmental 
Protection Agency, Washington, D.C. 

58. Klima, E.F., R.J. Zimmerman, T.J. Minello, and J.N. Nance, (in prep.). Wetland losses and fisheries 
production gains: a paradox in the northwestern Gulf of Mexico. National Marine Fisheries 
Service, Galveston, TX. 

59. National Weather Service, Galveston, TX. 

60. Texas Parks and Wildlife Department, Austin, TX, unpublished data. 

61. Texas Department of Water Resources. 1981. Sabine-Neches estuary: a study of the influence of 
freshwater inflows. Texas Dep. Water Res., Austin, TX, Publ. LP-116. 

62. Mueller, A.J., U.S. Fish and Wildlife Service, Houston, TX, unpublished data. 

63. Turner, R.E. 1976. Geographic variations in salt marsh macrophyte production: a review. 
Contrib. Mar. Sci. 20:47-68. 

64. Eubanks, T., Jr., Ornithology Group, Houston Outdoor Nature Club, Houston, TX, unpublished 
data. 


51 













































































Galveston Bay and the Surrounding 
Area: Human Uses, Production 
and Economic Values 

R. B. Ditton, D. K. Loomis, D. R. Fesenmaier, M. O. Osborn, D. Hollin, J. W. Kolb 1 


MEG WILSON—The Galveston Bay complex is adjacent to one of the most populated areas in 
Texas. It ranks first among urbanized areas in the state (1). With a 1980 population of 2,905,353, the 
Houston Standard Metropolitan Statistical Area (SMSA) ranks second only to the Dallas-Ft. Worth 
SMS A. Houston is the ninth largest SMSA in the U.S. (2). Of the 16 Standard Consolidated Statistical 
Areas (SCSA) in the U.S., Houston-Galveston ranks eighth (2). 

In 1980 nearly 2.8 million people lived in the four counties surrounding the bay (Chambers, 
Brazoria, Galveston and Harris), with 2.4 million in Harris county alone (Table 3.1). These four 
counties account for 75 percent of the population residing within the one-county coastal strata 
adjacent to the Texas coast, and 20 percent of the total state population. In comparison, 1,466,000 
persons (65 percent of the coastal population) lived in the four counties in 1960; this accounted for 
15.3 percent of the state population. Population growth will continue until at least the year 2000, when 
more than four million persons are projected to live in the Texas coastal area (3). At that time, it is 
projected that the four-county Galveston Bay area will account for 77 percent and 20 percent of the 
coastal and total state populations, respectively. 

Total personal income along the Texas coast is also heavily skewed towards the Galveston Bay 
area. Of $42 billion in personal income in the coastal counties in Texas, $35.5 billion (83 percent) is 
accounted for by the four counties surrounding Galveston Bay (Table 3.2). 

The purpose of this paper is to provide information on the extent to which Galveston Bay and its 
adjacent land area are used for various purposes and their respective economic values. In some cases, 
data are not available to demonstrate the extent of present use; data on level of infrastructure or some 
other indicator are used as proxies. Use and value are presented as a percentage of total activity for 
the Texas coast to put Galveston Bay in perspective, and where data are available, changes in 
Galveston Bay use levels and values over time are presented to understand trends. Finally, some 
findings regarding demographics and use are compared with those from other estuaries in the 
United States. In the following paragraphs, information is presented on seven major use categories 
for the Galveston Bay complex. 


Agriculture 

In 1982 there were 1,430,626 acres of farm land in the four counties surrounding Galveston Bay 
(Chambers, Brazoria, Galveston and Harris) or approximately 26 percent of the total farm acreage in 
the 16 Texas coastal counties. Between 1967 and 1982, there was a decrease of 297,374 acres (21 


’R.B. Ditton represents the Texas A&M University Department of Wildlife and Fisheries Sciences; D.K. 
Loomis, Texas A&M University Department of Recreation and Parks; D.R. Fesenmaier, Texas Agricultural 
Experiment Station; M.O. Osborn, Texas Parks and Wildlife Department; D. Hollin, Texas Sea Grant Program; 
and J.W. Kolb, Texas Water Commission. 


53 



Table 3.1. Distribution of Population Along Texas Coast and Percent Accounted for by the 
Galveston Bay Complex for the Years I960,1970,1980,1990 and 2000. 



I960* 

1970 b 

1980 c 

1990 d 

2000 d 

Jefferson 

245,659 

244,937 

250,938 

266,664 

272,346 

Chambers 

10,379 

12,187 

18,538 

21,310 

22,955 

Harris 

1,243,158 

1,741,908 

2,409,547 

3,078,356 

3,584,883 

Galveston 

140,364 

169,812 

195,940 

228,833 

246,490 

Brazoria 

72,204 

108,312 

169,587 

206,657 

235,848 

Matagorda 

25,744 

27,913 

37,828 

37,869 

34,057 

Jackson 

14,040 

12,975 

13,352 

14,392 

14,330 

Calhoun 

16,592 

17,831 

19,574 

24,694 

28,580 

Refugio 

10,975 

9,494 

9,289 

9,087 

8,309 

Aransas 

7,006 

8,902 

14,260 

20,012 

24,608 

San Patricio 

45,021 

47,288 

58,013 

66,780 

70,685 

Nueces 

221,573 

237,542 

268,215 

324,410 

380,285 

Kleburg 

30,052 

33,173 

33,358 

37,268 

39,501 

Kenedy 

884 

699 

534 

534 

586 

Willacy 

20,084 

15,570 

17,495 

19,845 

20,668 

Cameron 

151.098 

140.368 

209.727 

270,524 

318.384 

Total 

2,254,833 

2,828,911 

3,726,195 

4,627,235 

5,302,515 

Percent of coastal 
strata contained in 
four-county area 

65.0% 

71.8% 

75.0% 

76.4% 

77.1% 

Percent of state 
population contained 
in four-county area 15.3% 

18.2% 

19.6% 

20.0% 

20.1% 


Source: 

a«- 


percent) in the four-county area. Commercial fertilizer was used on 283,792 acres in the four counties 
at a cost of $8,711,000. The market value of agricultural products sold from the four counties in 1982 
was $113,747,000, with the vast majority from Harris (grains, nursery products and livestock) and 
Brazoria counties (grains) (4). 


Fisheries 


Commercial Fishing 

An estimated 425,000 pounds of finfish, with an estimated ex-vessel value of $206,000, were 
reported as harvested commercially from Galveston Bay in 1986 (Table 3.3). This represents 28 
percent of the Texas bay finfish production by weight and 21 percent by value. Galveston Bay also 
plays a major role in the Texas shellfish industry. More than 30 percent of the shrimp and blue crab 
harvested commercially from Texas bays are from Galveston Bay. Oysters from Galveston Bay, 
however, have the largest total ex-vessel value of any shellfish, nearly $7 million (67 percent of the 
state bay total). 

The annual inshore and offshore commercial fish landings (finfish and shellfish) along the Texas 
coast for 1986 was about 116 million pounds with an ex-vessel value of $246 million (5). Fesenmaier 
and Jones (6) report an average annual ex-vessel value of $205 million for inshore-offshore commer¬ 
cial fishing for the 1984-1986 period. Of this $205 million, the Galveston Bay complex accounted for 


54 









Table 3.2. Distribution of Personal Income During 1981 According to Coastal County, and 
Percent Accounted for by the Four-County Galveston Bay Complex. 


Income 


County 


(in thou.) 


Percent 

Jefferson 


2,709.2 


6.4 

Chambers 


201.7 


0.5 

Harris 


32,414.4 


76.0 

Galveston 


1,450.9 


3.4 

Brazoria 


1,390.4 


3.3 

Matagorda 


267.6 


0.6 

Jackson 


59.4 


0.1 

Calhoun 


220.0 


0.5 

Refugio 


58.6 


0.1 

Aransas 


67.0 


0.2 

San Patricio 


314.6 


0.7 

Nueces 


2,306.3 


5.4 

Kleburg 


196.8 


0.5 

Kenedy 


5.0 


<0.1 

Willacy 


50.8 


0.1 

Cameron 


945.4 


22 

Total 


42,658.1 


100.1 

Source: 17. 






Table 3.3. Estimated Commercial Harvest of Finfish and Shellfish from Galveston Bay Dur- 

ing 1986. 






Pounds 

% of all bays 

Ex-vessel 

% of all bays 


Harvested 

total weight 

value 

ex-vessel value 

Finfish 

424,495 

28 

206,491 

21 

Shellfish 





Shrimp 

6,152,860 

30 

6,839,741 

27 

Oyster 

3,538,808 

63 

6,951,738 

67 

Blue crab 

3,018,315 

32 

1,028,097 

33 


Source: 25. 


$63.6 million, or 31 percent (Table 3.4). This activity generated approximately $18 million in personal 
income. Gross personal income in Texas attributed to commercial fishing in Galveston Bay and 
supporting sectors resulted in state tax revenues of $2.8 million and taxes paid to local governments 
statewide of $4.4 million. 

The Texas Department of Water Resources (7) reported a much higher value for the Galveston Bay 
commercial fishery in 1976. In their report, Galveston Bay accounted for $115 million (43 percent) (in 
1986 dollars) of the total commercial landings coastwide (Table 3.5). 

Sport Fishing 

Recreational boat fishermen landed 3.2 million pounds of finfish from Texas bays during 1986. Of 
the total, more than 1.1 million pounds (35 percent) were landed in Galveston Bay (Table 3.6). This 
proportion has remained steady for the previous three years. Landings by shore-based fishermen are 
not available. 

Sport fishing expenditures associated with the Galveston Bay estuary account for approximately 


55 







Table 3.4. Direct and Total* Economic Impacts of the Inshore and Offshore Commercial 
Fishery in the Galveston Bay Complex (Trinity-San Jacinto Estuary), 1986. 

Total 

Landings Inshore Inshore/Offshore 



Inshore 

Inshore/ 

Offshore 

Regional 

State 

Regional 

State 

Output 
(Million $) 

12.5 

63.6 

32.9 

41.1 

167.6 

209.3 

Income 
(Million $) 

3.5 

18.0 

7.3 

10.4 

37.2 

52.7 

State Tax Revenues 
(Million $) 

0.1 

0.3 

b 

0.6 

b 

2.8 

Local Tax Revenues 
(Million $) 

0.1 

0.4 

b 

0.9 

b 

4.4 


*Total = direct, indirect and induced 
b Data not available 

Source: 6. 


Table 3.5. Direct and Total* Economic Impact of Commercial Fishing, Galveston Bay Com¬ 
plex (Trinity-San Jacinto Estuary), 1976 b . 


Total 


Output 
(Million $) 

Fishing Sector 

115.0 

Regional 

244.2 

State 

358.0 

Income 
(Million $) 

38.3 

81.3 

98.4 

State Tax Revenues 
(Million $) 

0.4 

2.3 

3.2 

Local Tax Revenues 
(Million $) 

0.5 

4.0 

4.5 


“Total = direct, indirect and induced 
b In 1986 dollars 

Source: 7. 


Table 3.6. 

Annual Weight of Finfish Landed by Recreational Boat Fishermen from Galveston 
Bay During 1984,1985 and 1986. 

Year 

Galveston Bay 

All Texas 

Bays 

% of total weight 
from Galveston Bay 

1983-1984 

1,391,100 

4,316,900 

32 

1984-1985 

940,700 

2,922,000 

32 

Source: 5. 





56 















one-half of all sport fishing expenditures in the Texas coastal bay systems (6). Sport fishing 
expenditures in the local area surrounding the Galveston Bay estuary during 1986 were over $171 
million. Gross Texas business in 1986 resulting from the sport fishing use of Galveston Bay totaled 
$576.7 million (Table 3.7). An additional $10 million was spent outside the region within Texas. 
Regional households received an annual income of $104 million from the sport fishing business in the 
area. Gross personal income in Texas attributed to sport fishing in the Galveston Bay complex was 
estimated at more than $154 million, resulting in state taxes of $7.8 million and taxes paid to local 
governments statewide at $13.9 million. 


Table 3.7. Direct and Total* Economic Impact from Sport Fishing Expenditures, Galveston 
Bay Complex (Trinity-San Jacinto Estuary), 1986 b . 



Direct* 

Regional 

State 

Total 

Regional 

State d 

Output 
(Million $) 

171.5 

181.2 

433.2 

576.7 

Income 
(Million $) 

53.6 

66.1 

104.0 

154.5 

State Tax Revenues 
(Million $) 

e 

0.8 

7.4 

7.8 

Local Tax Revenues 
(Million $) 

•Total = direct, indirect and induced 

2.3 

13.1 

13.9 


b Values in 1986 dollars 

c Direct impacts for the region and state differ due to the travel expenditure adjustment 
d Statewide expenditures include the regional impacts 
e Data not available 
Source: 6. 


Table 3.8. Direct and Total* Economic Impact from Sport Fishing Expenditures, Galveston 
Bay Complex (Trinity-San Jacinto Estuary), 1976-1977 b . 


Direct* Total 



Regional 

State 

Regional 

State* 1 

Output 
(Million $) 

7.7 

7.9 

17.7 

25.8 

Income 
(Million $) 

2.8 

3.0 

5.2 

7.3 

State Tax Revenues 
(Million $) 

e 

0.1 

0.2 

0.3 

Local Tax Revenues 
(Million $) 

e 

1.0 

0.3 

0.4 


•Total = direct, indirect and induced 
b Values in 1986 dollars 

c Direct impacts for the region and state differ due to the travel expenditure adjustment 
Statewide expenditures include the regional impacts 
'Data not available 
Source: 7. 


57 






These figures are much higher than those reported by the Texas Department of Water Resources. 
In 1976, sport fishing expenditures in the Galveston estuary were reported to be nearly $8 million 
(in 1986 dollars) or about 9 percent of total sport fishing expenditures coastwide (7) (Table 3.8). 

Recreation and Tourism 

Galveston Bay is used for other recreational activities besides sport fishing by residents in 
adjacent counties and tourists attracted to the region for business and/or pleasure. These activities 
include pleasure boating, hunting, swimming, camping, picnicking and sightseeing among others. 
For these activities, use data are either not available at all or not available specific to Galveston Bay. 
However, it is possible to approximate the extent of pleasure boating activity through boat regis¬ 
trations and data on boating facilities. 

In 1986, there were 103,562 motorboats registered in four adjacent counties. This is 71 percent of 
the total number of pleasure craft registered in Texas coastal counties, or 24 percent of the motorboats 
registered statewide (8). Likewise, 38 (46 percent) of the boat ramps administered by the Texas Parks 
and Wildlife Department on the Texas coast are located in the four counties. This constitutes 27 
percent of their boat ramps statewide (8). Between 1976 and 1987, the number of marinas in 
Galveston Bay more than doubled from 18 to 40, while the number of wet slips grew three-fold from 
3066 to 9171 (9). In terms of Galveston Bay's importance to recreational boating in Texas today, 
Galveston Bay accounts for 30 percent of the total number of marinas on the Texas coast and 63 
percent of the total wet slips in commercial marinas. This has grown from a 1976 figure of 27 percent 
of total marinas and 56 percent of coastal wet slips (Table 3.9). 

Visitors participating in sport fishing and other recreational activities (hunting, picnicking, 
swimming, camping, pleasure boating and sightseeing) in the six estuaries on the Texas coast spent 
approximately $586 million during 1986 (6). Of this total, $364 million (62 percent) was spent by sport 
fishermen. Direct expenditures for "other recreation activities" in the Galveston Bay complex were 
$122.4 million, 55 percent of the total expenditures for this category for all bay systems on the Texas 
coast (Table 3.10). Gross Texas business resulting from tourism and recreational uses of the Galveston 
Bay complex amounted to $425.2 million. Gross personal income in Texas attributed to "other 
recreational activities" in the Galveston Bay complex and supporting sectors was estimated at $113.3 
million, state taxes at $5.7 million and taxes paid to local governments statewide at $10.1 million. 

Comparisons with data collected by the Texas Department of Water Resources (7) are not possible 
since the "other recreation" category was not included previously. 

Petroleum, Chemicals and Other Manufacturing 

The four-county study area surrounding Galveston Bay contained 85 percent (3,989) of the 
manufacturing establishments in the 16 Texas coastal counties (1). Although there were approxi¬ 
mately one-half as many establishments in 1963 (2,221), they nevertheless constituted 78 percent of 
the total in the coastal counties at that time. In 1982, the four counties accounted for about 22 percent 
of the total number of manufacturing establishments in Texas (10). 

Despite the popular perception that petroleum is Houston's largest and most valuable industry, 
the chemical and allied products industry ranks first in the Houston area in terms of value added 
by manufacturing ($5.0 billion) (10). This constitutes about 30 percent of the total value added by 
manufacturing in the Houston-Galveston SCSA (Galveston-Texas City, TX SMSA; Houston, TX 
SMS A). There are 301 establishments in the area with a total of 36,100 employees and a payroll of $1.1 
billion. The vast majority (89 percent) of the establishments in the four-county area are located in 
Harris County. 

Nearly one-half of the total chemical production in the U.S. takes place in the Houston area. More 
than 500 chemicals are produced there, including 55 percent and 34 percent of the total polypropylene 
and polyethylene production, respectively, in the U.S. Furthermore, 46 percent of the total U.S. 
production of ethylene and propylene takes place in Houston (11). 

Thirty percent of the U.S. petroleum industry is located in the area adjacent to the Galveston Bay 
complex (12). In the Houston area the petroleum and coal products industry ranks third in terms of 
value added by manufacturing ($2.2 billion) (10). This is about 13 percent of the total value added by 
manufacturing in the Houston-Galveston SCSA. There are 69 establishments in the SCSA with a total 


58 


Table 3.9. Number of Marinas and Wet Slips in Galveston Bay and for the Texas Coast, 1976- 



1987. 






Galveston Bay 

Galveston Bay as % 
of Total Coastal 

Coastal 

Texas 


# of Marinas Wet Slips 

Slips 

Marinas 

# of Marinas 

Wet Slips 

1976 

18 3,066 

56.1 

27.3 

66 

5,469 

1981 

21 4,151 

58.1 

25.6 

82 

7,150 

1985 

26 6,579 

61.5 

28.9 

90 

10,706 

1987 40 9,171 

Source: 26,27,28. 

62.9 

29.9 

134 

14,573 


Table 3.10. Direct and Total* Economic Impact from Other Recreation b Expenditures, 
Galveston Bay Complex (Trinity-San Jacinto Estuary), 1986 c 


Direct Total 


Output 

Regional 

State 

Regional 

State' 

(Million $) 

122.4 

131.8 

311.0 

425.2 

Income 
(Million $) 

38.2 

48.5 

74.5 

113.3 

State Tax Revenues 
(Million $) 

{ 

0.6 

5.3 

5.7 

Local Tax Revenues 
(Million $) 

f 

1.6 

9.5 

10.1 


“Total = direct, indirect and induced 

b Activities include hunting, picnicking, swimming, camping, pleasure boating and sightseeing 
c Values in 1986 dollars 

d Direct impacts for the region and state differ due to the travel expenditure adjustment 
“Statewide expenditures include the regional impacts 
f Data not available 
Source: 6. 


of 16,900 employees and a payroll of $557 million. The vast majority (81 percent) of these establish¬ 
ments in the four county area are located in Harris County. 

Level of infrastructure is an indicator of the extent to which the petroleum industry along the Texas 
coast is focused on Galveston Bay. Of 31 oil refineries on the Texas coast, 12 (39 percent) are located 
in the four-county study area, representing 44 percent of the coastwide oil refinery design capacity 
(13). This is approximately 17 percent of the total oil refinery design capacity in the Gulf of Mexico. 
Of the 74 gas processing plants on the Texas coast, 22 (30 percent) are located in the four counties. 
Thirty-two percent of the gas processing plant design capacity along the Texas coast is located in the 
four county area (13). Of the 38 pipelines originating from either state or outer continental shelf (OCS) 
waters along the Texas coast, 16 (42 percent) make landfall in the four county area. The vast majority 
of pipelines from state waters make landfall in Brazoria County while the vast majority from OCS 
waters make landfall in Galveston County. Gas pipelines in these areas range in diameter from 6" to 
24," with oil pipelines being 4" to 14" in diameter (13). 

Wastewater Discharge 

More than one-half (51 percent) of the 3756 wastewater permittees in the state of Texas in 1987 are 


59 






Table 3.11. Number of Wastewater Permittees in Galveston Bay Watershed. 

Area 

Number of Permits* 


Trinity Basin 

(above Lake Livingston Dam) 

519 


San Jacinto Basin 
(above Lake Houston Dam) 

262 


Galveston Bay (below Livingston 
and Houston Dams) 

1,151 

(719) b 

Domestic 

674 

(484) 

Industrial 

477 

(235) 

Total Galveston Bay Watershed 

1,932 


Total Permittees in Texas 

3,756 


‘These include both active and inactive permits. "No discharge" 
b These include only discharging active permittees. 

permits are not included. 

Source: 14. 




located in the Galveston Bay watershed (Table 3.11). About 31 percent are in the immediate vicinity 
of the Bay (below the Lake Livingston and Lake Houston Dams). Not all of these are active permits 
involving wastewater discharge. In the vicinity of the Bay are 484 active domestic permittees 
discharging 1.5 billion gallons/day and 235 active industrial permittees discharging 36.5 billion 
gallons/day. In 1970 there were 139 self-reporting domestic permittees and 160 self-reporting 
industrial permittees in the vicinity of the Bay (comparable area to that used in 1987). Increases in the 
number of domestic and industrial wastewater permittees between 1970 and 1987 were 248 percent 
and 47 percent, respectively (14). No data regarding volume of wastewater discharged in the study 
area were available for 1970. 


Transportation and Navigation 

Nationally, the Port of Houston is the third largest in the contiguous 48 states in terms of total 
shipping tonnage. Access to the Port is provided from Galveston Bay westward along the 50 mile- 
long Houston Ship Channel to the turning basin in Houston's Central Business District. 

The Port of Houston is the leading port in Texas in terms of 1986 shipping tonnage (102 million 
tons), more than twice as much as the next competitor (Port of Corpus Christi). The Port of Galveston 
ranks seventh among eleven Texas ports with 8.2 million tons. Together, these two ports account for 
approximately 43 percent of the total tonnage along the Texas coast (15). In 1986,4817 ocean-going 
vessels (import or export) docked at the Port of Houston while 430 docked at the Port of Galveston 
(15). Total revenue generated by the Port of Houston was $3.0 billion in 1986 (16), nearly six times that 
generated by the Port of Galveston (Table 3.12). Two commodity groups (petroleum and liquid bulk) 
accounted for a majority of the total 1986 revenue in the Port of Houston. Grain accounted for almost 
one-half the total revenue and tonnage for the Port of Galveston. No estimates of the economic 
impacts of revenue generated by the ports on the region and state are available. Martin O'Connell 
Associates (16) argue that personal income is a better measure of the ports' economic value to the state 
and local economies than total revenue since monetary impact is specific to the state. 

The Ports of Houston and Galveston are major sources of income and employment for the region. 
Estimated total employment impacts to regional economies were 6,993 and 47,781 full time equiva¬ 
lents for the Ports of Galveston and Houston, respectively. In 1981 gross personal income in the 
region attributed to the Ports of Galveston and Houston was $336 million and $1.6 billion, respec¬ 
tively. 


60 







Table 3.12. Direct and Total* Economic Impact from the Ports of Houston, 1986 and Galveston 
1981 b . 


Direct Total 



Port of 
Galveston 

Port of 

Houston 

Port of 
Galveston 

Port of 
Houston 

Revenue 
(Million $) 

638 

2,976 

N/A 

N/A 

Employment 

(Man-years) 

4,138 

28,650 

6,993 c 

47,781 

Income 

184 

712 

405 d 

1,567 


(Million $) 

“Total = direct and indirect 
b Values in 1986 dollars 

“"Secondary employment derived using a 1.69 employment multiplier for waterborne transpor¬ 
tation (TDWR, 1983) 

d Secondaiy income derived using a 2.2 income multiplier recommended by the U.S. Depart¬ 
ment of Commerce Maritime Administration (1980) 

Source: 

1. Port of Galveston figures were derived from U.S. Army Corps of Engineers, Galveston District, 1987. 

2. Port of Houston figures from 16. 


Other Uses 


Housing 

The four counties surrounding Galveston Bay contained 1,135,271 (77 percent) of the housing units 
in the 16 Texas coastal counties in 1980 (17). This pattern was much the same in 1960 when these 
counties contained 487,076 (67 percent) of the housing units coastwide (18). According to recent data 
collected by the U.S. Bureau of the Census, Chambers, Brazoria, Galveston and Harris counties 
accounted for 66 percent of the building permits issued for single and multi-unit housing on the Texas 
coast between January-October 1987 (19). 

Military 

One of eight new Homeport naval installations nationwide will be developed in Galveston 
beginning in 1988. Eventually, two frigates, two mine sweepers and one patrol boat will be based 
there. Federal and local investment in facility development will be approximately $33 million and $3 
million, respectively. Direct expenditures for ship repairs and related business in the local area will 
be an estimated $11 million with a total economic impact on the region of $25 million. The payroll for 
the estimated 650 persons (ship and land-based personnel) associated with the base will be 
approximately $16.5 million (20). 

Galveston Bay in National Perspective 

When Galveston Bay is compared with thirteen other estuarine areas studied by Nixon (21), it 
ranks eighth in watershed area and fourth in surface area (behind Chesapeake Bay, Long Island 
Sound and Delaware Bay, respectively) (Table 3.13). Of 92 estuarine areas in the U.S., only 25 had a 
larger total drainage area than Galveston Bay (22). In terms of number of square kilometers devoted 
to industrial activity (light to heavy manufacturing) among the 92 estuarine areas studied, the Gal¬ 
veston Bay area (24) ranked third behind San Francisco Bay (337) and San Pedro Bay (249) (7). Al¬ 
though the Galveston Bay area was ranked among the top six estuarine areas studied by Nixon in 
terms of 1980 population levels (Figure 3.1), population density is not high due to the extensive acre¬ 
age in the four counties adjacent to the Bay (Table 3.14). It was impossible to make comparisons be¬ 
tween bay systems regarding the economic value of various uses due to the lack of available 
standardized data. 


61 





1860 1880 1900 1920 1940 1960 1980 


YEAR 


Figure 3.1. Human population adjacent to selected estuarine study areas. 

Source— 

All data except for Galveston Bay were derived from 21. Data for Galveston Bay counties are from 29. 


62 








Table 3.13. Approximate Physical Dimensions of Selected Estuarine Study Areas. 


Watershed 

Surface 


fy 



Area, KM 2 

Ranking 

Area, KM 

Ranking 

Galveston Bay 

32,510 

8 

1,600 

4 

Narragansett Bay 

4,800 

10 

285 

12 

Long Island Sound 

42,000 

4 

3,200 

2 

New York Bay 

38,000 

5 

390 

10 

Delaware Bay a , 

33,000 

7 

1,942 

3 

Chesapeake Bay 

110,000 

2 

11,500 

1 

Patuxent Estuary 

2,200 

12 

122 

15 

Potomic Estuary 

38,000 

5 

1,251 

5 

Pamlico Estuary 

11,000 

9 

305 

11 

Apalachicola Bay 

44,000 

3 

210 

13 

Mobile Bay 



1,070 

7 

Barataria Bay 

4,000 

11 

176 

14 

San Francisco Bay C 

160,000 

1 

1,240 

6 

Suisun Bay plus San Pablo Bay 



445 

9 

South Bay 



490 

8 

Kanaohe Bay 

97 

13 

32 

16 


“Below Smyrna River 
b Including tributaries 
including mud flats 

Source: All data except for Galveston Bay were derived from 21. Data for Galveston Bay are from 7. 


Table 3.14. Population Density (People/Acre) Surrounding Estuarine Study Areas. 


Galveston Bay 

Population Density 

1.0 

Ranking 

9 

Narragansett Bay 

1.5 

3 

Long Island Sound 

1.1 

8 

New York Bay 

3.2 

2 

Raritan Bay 

1.5 

3 

Delaware Bay 

0.3 

11 

Chesapeake Bay 

1.2 

7 

Patuxent Estuaiy 

0.4 

10 

Potomic Estuary 

0.1 

13 

Pamlico Estuary 

<0.1 

14 

Apalachicola Bay 

0.3 

11 

Mobile Bay 

1.5 

3 

Barataria Bay 

2.3 

3 

San Francisco Bay 

4.6 

1 


Source: All data except for Galveston Bay were derived from 21. Data for Galveston Bay are from 1,17. 


63 






Acknowledgments 

We acknowledge the many individuals and groups that contributed information in support of this 

paper. Slides in support of the oral presentation were contributed by Bob Nailon, Mel Russell, 

Dewayne Hollin, Joe Kolb, Villere Reggio and the Texas A&M Sea Grant College Program. 

References 

1. U.S. Department of Commerce. Bureau of the Census. 1983a. Census of Population: 1980. 
General Social and Economic Characteristics. Final Report PC(2)-C45 Texas. U.S. Government 
Printing Office. Washington, D.C. 

2. U.S. Department of Commerce. Bureau of the Census. 1981. Census of Population: 1980. General 
Social and Economic Characteristics. Final Report PC80-1-Cl. United States Summary Report. 
U.S. Government Printing Office. Washington, D.C. 

3. Texas Department of Health. 1986. Population Projections: 1960, 1970-2000. State Health 
Planning and Resource Development. Population Data System. Austin. 

4. U.S. Department of Commerce. Bureau of Census. 1984.1982 Census of Agriculture. Vol. 1, 
Geographic Area Series, Part 43, Texas: State and County Data. Washington, D.C.: U.S. Govern¬ 
ment Printing Office. 

5. Osbum, H. R. and M. O. Ferguson. 1987. Trends in Finfish Landings by Sport-boat Fishermen 
in Texas Marine Waters, May 1974-May 1986. Management Data Series Number 119. Austin: 
Texas Parks and Wildlife Department, Coastal Fisheries Branch. 

6. Fesenmaier, Daniel R. and Lonnie L. Jones. 1987. Regional and Statewide Economic Impacts of 
Sport Fishing, Other Recreational Activities, and Commercial Fishing Associated with Major 
Bays and Esturaies of the Texas Gulf Coast. Unpublished Manuscript Available from Authors, 
Texas A&M University. 

7. Texas Department of Water Resources. 1981. Trinity-San Jacinto Estuary: A Study of the 
Influence of Freshwater Inflows. LP-113, Austin. 

8. Grabowski, Jim. 1988. Texas Parks and Wildlife Department, Administrative Services Division. 
Telephone communication, Jan. 25. 

9. Hollin, Dewayne. 1987. Texas Recreational Boating Facilities Database. College Station: Texas 
A&M University Sea Grant College Program. 

10. U.S. Department of Commerce. Bureau of Census. 1985.1982 Census of Manufacturers. MC82- 
A-44. Geographic Area Series, Texas. Washington, D.C.: U.S. Government Printing Office. 

11. Syal, Sadat. 1988. Houston Economic Development Council. Telephone communication, Jan. 25. 

12. Kasdorf, Skip. 1988. Houston Chamber of Commerce. Telephone communication, Jan. 25. 

13. U.S. Department of the Interior. Minerals Management Service. 1987. Historic Leasing and 
Infrastructure, Visual No. 1. Metairie, Louisiana: Gulf of Mexico OCS Regional Office. 

14. Kolb, Joe. 1987. Texas Water Commission. Written communication, Nov. 10. 

15. Whitehouse, Vivian. 1988. Port of Houston. Telephone communication, Jan. 20. 

16. Martin O'Connell Associates. 1987. The Economic Impact of the Port of Houston. Bethesda, MD. 

17. U.S. Department of Commerce. Bureau of Census. 1983b. County and City Data Book. Washing¬ 
ton, D.C.: U.S. Government Printing Office. 

18. U.S. Department of Commerce. Bureau of Census. 1967. County and City Data Book. Washing¬ 
ton, D.C.: U.S. Government Printing Office. 

19. Minich, Pam. 1988. National Association of Homebuilders, Houston. Telephone communica¬ 
tion, Jan. 20. 

20. Hunter, Mel. 1988. Galveston Small Business Center. Telephone communication, Jan. 27. 

21. Nixon, Scott W. 1983. Estuarine ecology- a comparative and experimental analysis using 14 
estuaries and the Merl microcosms. Final Report to the U.S. Environmental Protection Agency, 
Chesapeake Bay Program. Kingston: University of Rhode Island, Graduate School of Oceanog¬ 
raphy. 


64 


22. U.S. Department of Commerce. National Oceanic and Atmospheric Administration. 1987. 
National Estuarine Inventory. Washington, D.C.: U.S. Government Printing Office. 

23. Dallas Morning News. 1961. Texas Almanac and State Industrial Guide 1961/1962. Dallas: A. 
H. Belo Corp. 

24. U.S. Department of Commerce. Bureau of the Census. 1972. Census of Population: 1970. General 
Social and Economic Characteristics. Final Report PC(1)-C45 Texas. U.S. Government Printing 
Office. Washington, D.C. 

25. Osbum, H. R., W. D. Quast and C. L. Hamilton. 1987. Trends in Texas Commercial Fishery 
Landings, 1977-1986. Management Data Series Number 131. Austin: Texas Parks and Wildlife 
Department, Coastal Fisheries Branch. 

26. Crompton, J. L., D. D. Beardsley and Robert B. Ditton. 1976. Marinas on the Texas Gulf Coast. 
College Station: Texas Agricultural Extension Service. 

27. Hollin, Dewayne. 1985. Marinas Along the Texas Gulf Coast, Second Edition. College Station: 
Texas A&M University Sea Grant College Program. 

28. Hollin, Dewayne and Malon Scogin. 1981. Marinas Along the Texas Gulf Coast, A Directory. 
College Station: Texas A&M University Sea Grant College Program. 

29. Dallas Morning News. 1951. Texas Almanac and State Industrial Guide 1952/1953. Dallas: A. 
H. Belo Corp. 


65 





















































































































































Issues and Information Needs 


R.W. McFarlane, T.J. Bright, B.W. Cain, M. Hightower, J.J. Kendall, J. W. Kolb, 
A J. Mueller, P.F. Sheridan, C.B. Smith, E.G. Wermund, T.E. Whitledge 1 


R.W. McFARLANE—Galveston Bay today is a sea of controversy, as proponents of development 
and protectors of natural resources challenge opposing claims of no-effect and environmental 
calamity. Any large, heavily industrialized city adjacent to an estuary will eventually impinge on the 
water quality of the waterway. A review of existing conditions and predictable changes in water 
quality of the Galveston Bay system must acknowledge that everything is connected to everything 
else, and it is impossible to do merely one thing. A change in one factor influencing the bay will 
automatically produce changes in other facets of bay dynamics. 

Population and industrial growth always produce byproducts, some of which are waste materi¬ 
als, and everything has to go someplace. The law of gravity ensures that material transport is 
downhill, and Galveston Bay will be a temporary repository for these waste materials as they 
inexorably move toward the Gulf of Mexico and beyond. Even substances that are removed by waste 
treatment procedures have not disappeared. It can be assumed that all waste products released into 
the environment may be transported by natural processes to places other than the point of release, 
and that many will be transformed into other chemical or physical forms during this process. Many 
of the chemicals will be incorporated into living organisms by the process of bioaccumulation, and 
some will be biomagnified to higher concentrations with each transfer along the food chain. As these 
chemicals interact with each other in the environment, they are likely to produce synergistic effects 
greater than any one of them could invoke acting alone. 

Finally, we must acknowledge that everything is constantly changing. Even if all development 
and population growth were to cease today, the components of the Galveston Bay ecosystem will 
continue to change. Our challenge is to sort out the effects of changes induced by man and identify 
those that need to be modified and minimized. We must carefully weigh the benefits of development 
projects against the costs to the commonweal. The continued health and productivity of Galveston 
Bay are in the best interests of everyone. 

The focus of our immediate concern is the ability of Galveston Bay to sustain, or enhance, its 
present commercial and sport fishery productivity and recreational value while facing numerous 
development projects (Table 4.1), underway or proposed, that can affect water quality. Some of these 
developments are large federal projects with potentially significant impacts. Others are small 
shoreline modifications proposed by private developers that, cumulatively, significantly reduce the 
acreage of shoreline wetland vegetation and productive bay bottom. The common thread that links 
all of them is the substantial population growth that the area has experienced. Population and 
industrial growth have increased the demand for natural resources and disposition of waste 
materials. 


Issues 

The critical issues associated with these projects are (1) water quality changes in the bay and its 
tributaries, which transport nutrients and both treated and untreated wastewater to the bay; (2) 


’R.W. McFarlane represents McFarlane & Associates; T.J. Bright and M. Hightower, Texas Sea Grant 
Program; B.W. Cain and A. Mueller, U.S. Fish and Wildlife Service; J. Kendall and J.W. Kolb, Texas Water 
Commission; P. Sheridan, National Marine Fisheries Service; C.B. Smith, Texas General Land Office; E.G. 
Wermund, Bureau of Economic Geology, The University of Texas at Austin; T.E. Whitledge, The University of 
Texas at Austin Marine Science Institute. 


67 



Table 4.1. Existing and Proposed Development Projects Affecting Galveston Bay. 


Navigation Projects 

Texas City Channel Enlargement 
Galveston Channel Enlargement 
Houston Channel Enlargement 
Liberty Channel Enlargement 
Gulf Intracoastal Waterway Enlargement 
Galveston Home Port 

Water Development Projects 

New Reservoirs 
Wallisville Lake 
Bedias 
Lake Creek 
Tennessee Colony 

Existing Reservoirs — Interbasin Transfer of Waters 
Luce Bayou (Trinity River to San Jacinto basin) 
Toledo Bend (Sabine River to San Jacinto basin) 
Flood Control Projects 

Buffalo Bayou and Tributaries 
San Jacinto River and Tributaries 

Shoreline Development Projects 
Industrial Shoreline Development 
Resource Extraction, Bay and Onshore 
Waterfront Housing Development 
Galveston Island Causeway 
Private Property Development 


reductions in freshwater inflow to the bay system and its associated wetlands, and subsequent 
changes in bay salinity; (3) enlargement and maintenance of navigation channels as regards dredged 
material disposal, increased turbidity, resuspension of toxic or hazardous chemicals, and changes in 
bay salinity profiles; (4) loss of contiguous wetlands due to subsidence, erosion or shoreline 
development; (5) energy production in a bay environment; (6) comprehensive assessment of 
cumulative impacts; and (7) ecosystem interconnections. The impact of possible changes on salinity, 
productivity, eutrophication, and public health will be discussed below. It may be necessary to 
consider changes and developments within the entire bay watershed (see Appendix I), 360 miles long 
and as much as 100 miles wide, inhabited by nearly 6 million people. The important questions to ask 
are these. How much has past development influenced the bay? How will current and proposed 
projects affect the bay? What will be the cumulative impact on the bay of existing projects functioning 
at their design capacity plus the proposed future projects? 

Water Quality 

Water quality is affected by natural variations in chemical concentrations within a water body, 
the accidental or deliberate discharge of natural or synthetic chemicals, thermal discharges, and the 
distribution and abundance of pathogens. The diversion of water within a drainage for human 
purposes and the subsequent return of much of this water as wastewater effluent affects the minerals 
and nutrients transported by the water before and after human use. Suspended and dissolved solids 
are removed by water treatment before distribution to consumers, potentially affecting the concen¬ 
trations of micronutrients that would have reached the bay. Treated wastewaters contribute 
substantial amounts of macronutrients to the bay. A certain amount of nutrient enhancement will 
stimulate bay productivity; an excessive amount could lead to eutrophication and reduced produc¬ 
tivity, at least in those products most useful to man. 

The distribution of total organic carbon (TOC) is positively correlated with the percentage of mud 


68 




Table 4.2. Distribution of Total Organic Carbon in Galveston Bay. 

Location 

High Values 


(percent) 

West Bay 

1.6 

East Bay 

1.8 

Galveston Bay 

1.9 

Trinity Bay 

2.4 

Buffalo Bayou/ 


Houston Ship Channel 

3.9 

Offatt Bayou 

4.0 

Galveston Channel 

5.7 

Source: (1) 



in bottom sediments. Highest concentrations of TOC occur in bay-center muds, and lowest in bay- 
margin sands. Upper bay concentrations (Trinity Bay) are greater than those found in the lower bays 
(West Bay, East Bay), as shown in Table 4.2. The highest concentrations of TOC, however, occur in 
channels characterized by deeper-water, wave-protected, and oxygen-deficient bottom sediments 
that locally serve as sinks for the accumulation of organic-rich muds (1). High concentrations are 
widely distributed in Trinity Bay, particularly near its head. The Trinity River and bay-head delta are 
probably the primary sources of the carbon. The Trinity River valley contains floodplain swamps and 
marshes that export organic carbon during floods. There is widespread concern that construction of 
the Wallisville dam near the mouth of the Trinity River will affect the transport of vital nutrients to 
the bay. More than 95 percent of carbon, nitrogen and phosphorus input to Galveston Bay arrives 
with freshwater inflow (2). The Trinity River alone provides half of all freshwater inflow to Galveston 
Bay. 

Eutrophication is an excess of dissolved nutrient concentrations in a body of water that produces 
a noticeable change in water quality that may range from simple discoloration to catastrophic events, 
such as fish kills. A whole host of intermediate eutrophication effects, such as changes in species 
composition of food organisms or "dead water" depleted of oxygen, may result. Historically, 
Galveston Bay has contained elevated concentrations of nutrients derived from discharges and non¬ 
point sources (3). Concentrations greater than National Academy of Science guidelines were accom¬ 
panied by severe oxygen depletion in the Houston Ship Channel (84 percent), Galveston Bay (12 
percent). Trinity Bay (4 percent), and West Bay (4 percent of the time), when judged against a 5 mg/ 
1 criterion (4). Light limitation from silt or suspended sediment may hamper plant growth in the 
vicinity of nutrient inputs. Freshwater inflows are responsible for the major portions of nutrient 
inputs to Galveston Bay (5) and light limitation apparently reduces the importance of phytoplankton 
in regions of the estuary that are turbid. 

Recent evaluation of nutrient loading by the Texas Water Commission (6) clearly showed a 
reduction of nutrient loading of nitrogen and phosphorus from 1976 to 1983, compared to the years 
1969 to 1975. The mean concentration of ammonia-N decreased from 0.154 to 0.079 mg/1, and ortho¬ 
phosphorus decreased from 0.463 to 0.293 mg/1. BOD reductions were also observed that produced 
high oxygen concentrations in previously impacted areas. Even though Galveston Bay waters have 
recently had smaller nutrient concentrations than previously measured in the 60s and 70s, their 
deleterious effects have not been eliminated since many non-point sources are not controlled (e.g., 
agricultural fertilization). Accidental or deliberate discharges are also often significant in small areas 
for short periods, as when sewage and sludge released into White Oak Bayou killed thousands of fish 
by oxygen depletion in September 1987. 

Sediments in waterways near industrial facilities generally have levels of heavy metals (arsenic, 
cadmium, copper, lead, mercury, nickel, tin and zinc) that exceed background levels for that 
waterway. Resuspension and redistribution of these contaminated sediments by ship traffic, tidal or 
wave action, and dredging operations are reasons to be concerned about the impact of heavy metals 
on the natural resources in Galveston Bay. Many of these heavy metals are bioaccumulated from the 
sediment by benthic infauna and epifaunas and some plant species. A number of factors, such as pH, 


69 




Table 4.3. Heavy Metal Concentrations in Galveston Bay Sediments. 



Proposed EPA 

Bay Sediments (muds, ppm) 


Screening 



Buffalo Bayou/ 


Level 


Bay 

Houston Ship Channel 

Metal 

(ppm) 

mean 

high 

high 

Chromium (total) 

100 

55 

120 

150 

Copper 

50 

28 

130 

160 

Lead 

50 

34 

140 

260 

Nickel 

50 

26 

113 


Zinc 

75 

89 

275 

590 

Source: 1. 






the chemical form of the metal, other chemicals or chelating agents, and the redox potential of the 
sediment, will influence the amount of bioaccumulation that will occur. 

Local concentrations of chromium, copper, lead, nickel and zinc can exceed the proposed 
screening levels for dredged-sediment disposal established by the U.S. Environmental Protection 
Agency (Table 4.3). Abnormally high trace metal concentrations in sediments at many locations 
probably result from anthropogenic contributions. Highest concentrations were found in channel 
sediments, such as the Buffalo Bayou/Houston Ship Channel and Texas City Channel, where 
industrial and municipal discharges have been reported and widely publicized previously (1). A 
probable source of trace metals in Trinity Bay and East Bay is the Trinity River, where higher than 
normal levels of heavy metal particulates have been reported in river water. Simulated flow patterns 
indicate that predominate net flow is from Trinity Bay around Smith Point into East Bay during 
several months of the year. 

Other, less obvious, sources of contaminants also impact the bay. Copper, for example, is a potent 
algacide and one very soluble form in estuarine water can have an impact on the phytoplankton 
community. Copper and tributyltin are used in antifouling paints on ships, bulkheads and sub¬ 
merged structures. Tributyltin leaches from these paints and is so toxic to shellfish that Virginia, 
Maryland and several European countries have banned this compound. Concentrations in water as 
low as 1 part per trillion can adversely affect the reproductive cycle of oysters. Hundreds of fishermen 
and pleasure boaters on Galveston Bay are now painting their boats with the repellent. Oysters 
recently collected from four locations in Galveston Bay contained 120 to 1,000 parts per billion 
tributyltin. 

Hundreds of petroleum compounds (aliphatic and aromatic hydrocarbons) are discharged, 
dumped or spilled each day into the Galveston Bay system. These petroleum compounds vary in 
their toxicity to bottom-dwelling organisms and juvenile stages of shellfish and finfish. Generally, 
these compounds do not cause visible fish kills, but they are likely to induce liver damage and 
promote tumor growth in fish. There are more than 200 oil and gas wells in or near Galveston Bay 
that produce up to 8 barrels of saltwater for each barrel of oil. This wastewater (brine or produced 
water), discharged into the bay system, is heavily contaminated with water soluble fractions of oil 
as well as small droplets of crude oil. More than 1 million barrels of produced water are discharged 
per day. At the permitted level of 20 ppm oil, there is a minimum of 20 barrels of oil per day being 
discharged into the bay system. These oil droplets generally get bound to sediment particles in the 
water and settle into the sediment layer. Benthic organisms are excluded from these discharge points 
in all directions for up to 50 meters. Petroleum hydrocarbons can be accumulated by living organisms 
but biomagnification is rare. These hydrocarbons are known to be metabolized in the liver and form 
reactive intermediate compounds that are carcinogenic and also disrupt the mixed-function oxidase 
systems in vertebrates. Reduced production and survivability is the end result of chronic exposure 
to petroleum hydrocarbons. 

Sediments in many shellfish and finfish nursery areas also contain industrial contaminants, for 
example, petroleum waste hydrocarbons such as chlorinated phenols, chlorinated styrenes, phtha- 
late esters, and degreasing solvents. These chemical compounds are potent biocides, long-lasting in 


70 





Table 4.4. Number of Wastewater Permittees in Galveston Bay Watershed. 

Area 

Number of Permits 

Trinity Basin 


(above Lake Livingston Dam) 

519 

San Jacinto Basin 


(above Lake Houston Dam) 

262 

Galveston Bay 


(below Livingston and Houston Dams) 

1,151 

Total Galveston Bay Watershed 

1,932 

Total Permittees in Texas 

3,756 


sediments, and lipophilic. Lipophilicity implies that the compound can be stored in fat tissues and 
transferred throughout food chains. 

Galveston Bay receives runoff from large agricultural and municipal areas that may contain 
pesticides. Fields used for rice, soybean and sorghum production regularly are sprayed with 
herbicides and organophosphorus pesticides. Rice farming procedures typically keep the rice 
flooded during the growing season, which enhances runoff during these months. Mosquito abate¬ 
ment programs along the shoreline of Galveston Bay are another source of organophosphorus 
insecticides. These programs are usually implemented during the spring and summer months, 
coinciding with the entrance of juvenile crabs, shrimp and fish into the marshes. Most organo- 
phosphates are extremely toxic to juvenile stages of aquatic organisms. A third source of pesticides 
entering the bay is runoff from urban areas. Tons of these chemicals are applied by professional lawn 
care services, pest control services, and individual landowners. Herbicides and insecticides are 
applied to gardens, flower beds and drainage ditches. Chlordane is used as a termiticide around 
residences. Texas Department of Agriculture data indicate that residential runoff transports more 
pesticides into rivers than farmland. 

There are 3,756 permitted wastewater discharge outfalls in Texas. Fifty-one percent (1,932) of 
them discharge into the Galveston Bay watershed (Table 4.4). Thirty-one percent (1,151) discharge 
in the immediate vicinity of the bay. The chemical and biological oxygen demands of wastewater 
effluents and untreated discharges into tributaries and the Houston Ship Channel can drastically 
lower or eliminate dissolved oxygen concentrations and negatively impact fishes and bottom¬ 
dwelling organisms in particular. In addition to the chronic exposure and the continuous or 
intermittent discharge of contaminants, bay inhabitants are also subjected to episodic petroleum and 
chemical spills. Segments of a number of bay tributary streams have been designated as "unfishable, 
unswimmable." Bacterial contaminants from sewage treatment plants and urban runoff have 
frequently closed down oyster harvesting. Approximately 51 percent of the bay is permanently 
closed to shellfish harvesting. Toxicants and carcinogens potentially can be introduced into human 
food chains. 

Has past development and waste disposal influenced the biota of Galveston Bay? The issue is 
difficult to resolve with certainty. As seen in Table 4.4, the species richness of benthic macroinverte¬ 
brates varies considerably in different segments of the bay. West Bay exhibits the greatest diversity. 
Lower Galveston Bay has a richer biota than upper Galveston Bay. The fauna of East Bay seems 
surprisingly low. Trinity Bay, which experiences the lowest salinity and greatest fluctuations in 
environmental conditions, appears to be a naturally stressed community. One clam, Rangia cuneata, 
was considered to be a dominant species in Trinity Bay in the early 1970s but appears to have 
disappeared from many areas, although dead shells occur in all bays (1). Neither polychaetes nor 
mollusks live in the San Jacinto River or Houston Ship Channel; one crustacean persists in the ship 
channel. 

Information Needs 

There are many unresolved questions regarding biogeochemical cycling in Galveston Bay. What 
are the concentrations and locations of arsenic, cadmium, mercury, selenium and toxic organics that 
have yet to be measured? Does the concentration and distribution of pollutants change over time? 
What is the extent of heavy metal contamination in nursery areas receiving urban runoff, industrial 


71 



runoff and anti-fouling paint (tributyltin) from marinas? What is the extent of heavy metal contami¬ 
nation in nursery areas by discharge of oil production water? What are the effects of production water 
on larval stages of crabs, shrimps, oysters and fishes? What are the impacts of production water 
discharged on wintering waterfowl food items? What is the composition of non-point runoff from 
agricultural areas? How are contaminants partitioned in the nursery areas? What is the extent of 
contamination from maintenance dredged material put in confined disposal areas that drain into the 
bay? What are the dynamics of contaminants in dredged spoil disposal areas as they dry out and then 
receive precipitation? What is the extent of contaminant remobilization caused by dredging and 
other bottom disturbances? What are the transfer coefficients for the uptake of sediment contami¬ 
nants by the biota? How are toxic contaminants degraded in sediment and water? What are the effects 
of toxicants on endocrinology and reproduction? What are past, current and projected petroleum and 
chemical spill rates? What were the environmental consequences of past spills? What are the 
biological effects of eutrophic and hypoxic events? Wha t are current nutrient levels in the bay, at what 
point would nutrients become excessive, and is this likely to occur in the near future? Do anoxic 
conditions reach the bay itself? Are there any temporary circumstances that extend the anoxic zone? 
What is the near-future prognosis regarding bacterial contamination —improvement, deterioration, 
no change? Would the proposed increase in dredging activity produce a real threat to human health? 
Do any thermal effluent outfalls constitute a public hazard regarding thermophilic pathogens? Are 
toxicant levels in human food species a threat to human health? 

How important are nutrients in freshwater inflow to the maintenance of our estuaries as we know 
them today? If nutrients in the freshwater were reduced by a factor of 10, would the resultant effect 
be linear or non-linear? Would plant growth be reduced enough to affect the feeding of animal 
populations?? What is the relative importance of in-situ regeneration of nutrients compared to inputs 
to such shallow estuaries? How do the roles of point and non-point sources compare? Do non-point 
sources provide different chemical species than point sources? Does a smaller yet highly impacted 
region around a point source produce a mini-environment of eutrophication with more lethal effects 
on plant or animal life than non-point sources? What is the short-term temporal behavior of nutrient 
species that influence primary production processes? Do nutrients display diurnal behavior related 
to other biological processes, like denitrification, nitrification or decomposition? Are microalgae and 
phytoplankton species nutrient-limited in Galveston Bay, or do other factors control their growth? 

Freshwater Inflow 

Galveston Bay is connected to the Gulf of Mexico through two natural entrances, Bolivar Roads 
and San Luis Pass, and man-made Rollover Pass. Without freshwater input, tidal action would 
produce equal salinities in both bay and gulf, 35 parts per thousand (ppt, or 3.5 percent) salt. The 
amount of precipitation that falls on the bay exceeds the volume of water that evaporates from the 
bay surface by 6 inches, and precipitation accounts for 14 percent of all freshwater that reaches the 
bay. Thus, precipitation alone would lower bay salinity but an equal amount of water enters from the 
San Jacinto River, 25 percent of the input drains from the surrounding shoreline, and 48 percent of 
all freshwater inflow enters from the Trinity River alone (see Appendix I). The average amount of 
freshwater that enters the bay each year is sufficient to totally replace the volume of water in the bay 
more than four times. 

The salinity gradient in Galveston Bay is highly dynamic, responding to brief environmental 
changes, such as heavy precipitation events and frontal passages, or extended changes, such as 
droughts. Passage of a cold front, accompanied by strong northerly winds, has dropped surface 
salinity at Bolivar Roads from 18 ppt to 0.5 ppt as water was pushed out of the bay, and rebounded 
to 25 ppt as gulf waters flooded back in, all within 29 hours (7). Although the bay system is shallow 
throughout, vertical salinity gradients are common, particularly in the navigation channels. Differ¬ 
ences as great as 5 ppt can occur in water only 3 feet deep, or 15 ppt in the 40-foot deep channel (8). 
The efficacy of two-dimensional salinity modeling is questioned when the model fails to predict 
salinities as high as historical records. Other calculations have predicted that salinities could reach 
28 ppt in Trinity Bay when authorized water rights are fully exploited during periods of low Trinity 
River flow. Salinity increases of this magnitude could seriously affect oyster productivity. 
Information Needs 

How will changes in salinity affect the distribution of living organisms in the secondary bays 
(Trinity, East, West)? Will increased salinities permit the persistence of oyster pathogens and 
predators, thus reducing oyster productivity? How will full utilization of authorized water yields for 


72 


Lake Livingston and Wallisville Lake affect salinity in Trinity Bay? If large volumes of water are 
transferred from Toledo Bend Reservoir and the Sabine River to the San Jacinto River drainage area 
as municipal and industrial water for Houston, how will the increased flow of wastewater discharge 
affect the bay? Would a three-dimensional salinity model more accurately portray future salinity 
gradients; if so, would the difference between model outputs justify the substantial investment of 
time and funds required to develop and verify the three-dimensional model? 

Navigation Channels 

Galveston Bay is a drowned river valley that has nearly filled with sediment from the Trinity and 
San Jacinto Rivers and smaller tributaries. Averaging only 7 feet in depth, bottom sediments are 
highly susceptible to wind-driven wave action and shrimp trawling that increase turbidity. Current 
ship channel maintenance dredging, and proposed channel enlargement and subsequent mainte¬ 
nance dredging, threaten to substantially increase turbidity over broad areas simultaneously. 
Turbidity decreases the depth to which sunlight may penetrate the water and therefore may decrease 
the primary productivity that supports much of the food web. 

Two facts are certain. Dredging will continue to occur if Texas waterways are to remain open. 
Secondly, economic and environmental decisions relevant to dredge spoil disposal are currently 
being made without an adequate data base regarding the optimum ratios between habitats, i.e., 
emergent marsh areas, submerged grass beds, shallow-water and deep-water habitat categories. 
Historically, state and federal regulatory agencies have required that dredge spoil material be placed 
either in approved disposal sites at or above mean high water. In the Galveston Bay system, erosion 
and subsidence has resulted in the conversion of upland habitat into submerged habitat and the 
conversion of shallow-water habitat into deep-water habitat. Shallow-water habitats are known to 
be more productive than deeper waters. It may be beneficial to place clean dredged material into the 
bay system to convert deep-water areas into more productive shallow-water habitat and perhaps 
achieve a more balanced ecosystem. Conversely, the current practice of placing dredged material 
above mean high water may need to be continued. 

Information Need 

A comprehensive habitat analysis needs to be conducted to ascertain the historical versus present 
ratio of the various habitat categories in terms of acreage and productivity, i.e. emergent marsh areas, 
submerged grass beds, shallow-water and deep-water habitats, etc. An analysis of this sort could 
provide data that would be beneficial from both an environmental and economic perspective. What 
will be the effect of nearly doubling the ship channel cross section, from the existing 40 x 400-foot 
(16,000 square feet) to the proposed 50 x 600-foot (30,000 square feet) section, on bay salinity and 
flushing? What will a new 12-foot deep channel across Trinity Bay do to bay salinity? (See Appendix 
I.) What is the margin of error on the salinity model? What will be the effects of resuspending sediment 
contaminants? 


Loss of Shoreline Uplands and Wetlands 

The quantification of loss, or gain, of land caused by natural processes and human activities about 
Galveston Bay is a principal issue. The loss includes both uplands and wetlands. Land that is eroded 
returns to the bay and contributes to other principal issues, such as the geochemistry of the bay floor 
and sediment dynamics. While property losses measured in real estate values are an immediate 
concern to local citizens, the land lost to the natural system over many years provides better estimates 
of past and future losses. Shoreline monitoring of the Galveston-Trinity Bay System has demon¬ 
strated a shoreline retreat of 2.2 feet per year landward between 1850 and 1982, causing a loss of 8,000 
acres of land (9). Shoreline retreat has increased from 1.8 feet per year before 1930 to 2.4 feet per year 
since then. 

The principal natural processes that determine shoreline position are (1) changes in relative sea 
level, (2) waves from prevailing winds, (3) storm waves, including tropical cyclones and northers, (4) 
supply of sediment from streams, and (5) subsidence. Human activities that impact the relative 
positions of bay shorelines include (1) land fills, (2) riprap and seawalls, (3) size and orientation of 
dredged channels, and (4) subsidence caused by pumping water, oil and natural gas. 

The diversity and health of bottom-dwelling animals depends on the distribution of bottom 
sediment types and the turbidity, i.e. the suspension of sediments, in the water column. Sediments 
are the carriers of both nutrients and toxicants in bay systems. Certain sediment types, such as 
accumulations of dead animal shells or sand, are significant economic resources. Therefore, the 


73 


Table 4.5. Species Richness of Benthic Macroinvertebrate Assemblages. 


Location 

Mollusks 

Number of Species 
Polychaetes 

Crustaceans 

West Bay 

42 

48 

40 

Galveston Bay 

32 

41 

29 

East Bay 

9 

20 

14 

Trinity Bay 

7 

7 

3 

Clear Lake 

Houston Ship Channel 

1 

4 

2 

San Jacinto River 

Source: 1. 





Table 4.6. Galveston Bay Wetland Habitat Changes, 1956-1979. 


Change 

Acres Percent 


Wetland Habitat Type 

Estuarine Marsh 
Freshwater Marsh 

Estuarine Open Water 
Freshwater Open Water 

Wooded 

Streams 

Beach 


1956 

1979 

Acres 

Acres 

154,588 

130,139 

51,496 

39,119 

363,213 

388,397 

19,648 

21,939 

1,873 

6,267 

3,499 

3,835 

3,015 

1,413 


-24,449 

-15.8 

-12,377 

-24.0 

+25,184 

+6.9 

+2,291 

+11.7 

+4,394 

+234.6 

+336 

+9.6 

-1,602 

-53.1 


understanding of sediment dynamics becomes an important issue. The quantity of sediment 
contributed by streams, and where it is ultimately deposited, is inadequately known. We do not 
know where the sediments of eroded shorelines go or how they get there. Sediments are resuspended 
by waves but the details of the processes are not well known. Sediment is transported from the bay 
to the gulf and some is returned but the mass balance is not known. 

Subsidence, shoreline erosion and changes in riverine suspended sediments have all contributed 
to a general loss of wetlands. It can occur as small nibbles or the loss of large tracts, indirectly or by 
deliberate land-use conversion. Estuarine marshes provide shoreline stabilization, maintenance of 
water quality by filtration of upland runoff and tidal waters, nursery habitats for economically 
important estuarine-dependent fisheries, and detrital materials to the bay food web. The U.S. Fish 
and Wildlife Service classified and quantified the wetlands surrounding Galveston Bay in 1956 and 
again in 1979, using aerial photo interpretation techniques. Habitat changes detectable in this manner 
are shown in Table 4.6. Substantial areas of brackish and freshwater wetlands were lost during the 
23-year interval between surveys. 

Seagrasses, never prominent, have also suffered major declines in recent years. The exact causes 
for this precipitous decline in seagrass habitats, from 5,200 acres in 1956 to 250 acres by 1979, will 
never be fully understood. The rapid industrial and residential growth of the Houston-Galveston 
metropolitan area is the likely cause. Increases in turbidity, pollutant runoff, vessel and boat activity, 
and coastal development are all suspected factors. The northern widgeon grass beds in Trinity Bay 
declined after construction of a power plant. The Clear Lake-Kemah-Seabrook area has become 
heavily urbanized. The Gulf Intracoastal Waterway and its dredged material disposal sites run 
adjacent to former seagrass beds on the northern short of West Bay. At least six major housing 
developments along the northern shore of Galveston Island were built adjacent to once-thick 


74 







grassflats. Although sea grasses may never have been a major component of Galveston Bay, they have 
been nearly eradicated from the estuary in less than 30 years. 

Information Needs 

There are many unanswered questions regarding this issue. Is land loss inevitable? If so, can man 
gainfully control the rate? If predicted atmospheric changes cause a greenhouse effect and contribute 
to a steady rise in sea level, what will be the extent of upland and wetland losses in Galveston Bay? 
Can new wetlands be created as fast as shorelines subside or erode? Does shoreline erosion contribute 
nutrients or toxicants to the bay? Can we model the processes of dredging and spoil disposal? Can 
dredged material be used to overcome subsidence and maintain or create wetlands? Will marshes 
created by man function in a similar manner as natural marshes? How long a period is required for 
full functioning to appear? How do natural versus created, man-made marshes compare regarding 
primary productivity, faunal community development, and the physical and chemical characteris¬ 
tics of the substrate? Are wetlands critical for fishery species, or can their functions be replaced by 
other habitats? Is displaced open-water habitat critical to fishery organisms? Is there an optimal 
open-water to vegetated-bottom ratio for estuaries, and if so, does it vary with the type of fishery 
organism or geographic location? Where is the nearest sand resource for beach nourishment? 

Energy Production in Galveston Bay 

The existence of petroleum and natural gas production facilities within Galveston Bay poses some 
unique environmental problems. Normal production activities create a number of bottom distur¬ 
bances. During the exploration phase, seismic activities involve the drilling of shot holes, energy 
pulse damage to benthic and pelagic species, and the physical disturbance of benthic species due to 
"spuddown" of work barges and propwash as seismic vessels operate in shallow water (see Appen¬ 
dix I). Site preparation activities often require dredging of access channels to the drill site. The bay 
bottom is soft, unconsolidated fine-grained mud that will not support drilling platforms. Site 
preparation usually requires dredging down to a firm clay base, and covering the site with a 2-foot 
deep pad of dead oyster shell to support the drilling barge. This impacts the bottom-dwelling 
organisms and increases turbidity nearby. The installation and removal of pipelines further disturbs 
the bay bottom. 

Drilling operations involve the disposal of fluids into the water column. Water used to rinse drill 
bit cuttings is routinely discharged into the bay. Production water, the brine produced from the wells, 
is also discharged into the bay, and may contain up to 25 ppm hydrocarbon material under existing 
Railroad Commission rules. Rig cleaning is usually performed by using bay water under high 
pressure to wash-down drilling barges when the drilling operation is completed. Oils and grease are 
washed overboard, along with quantities of drilling muds, solvents, soaps, degreasers, lubricants 
and other materials. The predominant drilling mud used in Galveston Bay is a barite-based 
compound outlawed in California for both offshore and onshore drilling due to heavy metal 
contamination of marine and ground waters. When a well is completed and a barge-mounted drilling 
rig prepares to leave the site, the bilge water is pumped into the bay to re-float the rig. Derelict 
structures and equipment left on-site by developers results in safety hazards and possible pollution 
problems. On the positive side, platforms and underwater structures provide attachment points for 
aquatic organisms in an environment typically poor in available solid substrates. The placement of 
oyster shell for drilling pads may enhance and diversify benthic communities. 

Information Needs 

The current and future impacts resulting from the discharge of fluids from energy production 
facilities need to be determined. Are the ecological impacts of energy-related bottom disturbances 
biologically significant? What is the cumulative impact of the concentration of production sites 
within this small area? 

Comprehensive Assessment of Cumulative Impacts 

It is readily apparent that the Galveston Bay System has been, is and will continue to be subjected 
to a number of external impacts that potentially may affect its productivity. Simultaneously, demand 
for its resources is increasing as the surrounding human population continues to grow. All 
ecosystems have limits on their ability to assimilate impacts. Historically, these limits have typically 
been unknown or unheeded until they have been surpassed. Other major estuaries—Chesapeake 
Bay, Delaware Bay, San Francisco Bay—have suffered major, perhaps irreversible, declines in their 


75 


productivity as the result of excessive anthropogenic impacts. With Galveston Bay we have to 
opportunity to act—to identify and reduce or eliminate these impacts—before it is too late. 

The initial symptoms of stress have already appeared. The brown pelicans and other species have 
disappeared, oyster populations are greatly reduced, seagrasses are almost nonexistent, wetlands 
are being nibbled away around the entire bay periphery, sediment import has been drastically 
reduced, and freshwater inflow is threatened. Heretofore, each individual action has been judged 
independently, as if other development impacts do not exist. Clearly, consideration of the Galveston 
Bay ecosystem demands a holistic approach. 

Many environmental perturbations can produce cumulative effects (10). When materials, espe¬ 
cially toxicants, are added to the environment from multiple sources water quality can deteriorate, 
leading to changes in the species composition of the biota and alteration of the links in the food web. 
A second major type of cumulative effect can result from the repeated removal of materials or 
organisms from the environment. Intense fishery harvests, especially when combined with natural 
environmental changes, can lead to population collapse if a critical, usually unknown, threshold is 
passed. A third kind of cumulative effect can result from environmental changes over large areas and 
long periods, as, for example, extensive dredging operations and open-water spoil disposal that 
affect bottom habitat. More complicated cumulative effects arise when stresses of different types 
combine to produce a single effect or suite of effects. If channel enlargement was to resuspend 
toxicants and increase saltwater intrusion at the same time that freshwater inflow was reduced, 
salinity increases might permit invasion of oyster predators, parasites and pathogens and result in 
further inroads to an already depressed oyster population. Complex cumulative effects also occur 
when many individual areas in a region are repeatedly altered, as with periodic maintenance 
dredging and open-water spoil disposal. Large contiguous habitats can be fragmented into ever- 
smaller patches separated by inhospitable areas, making it difficult for organisms to locate and 
maintain populations in disjunct habitat fragments. 

Cumulative impacts may also occur when perturbations are crowded in time, so close together 
that the effects of one perturbation are not dissipated before the next occurs. Cumulative impacts also 
result from disruptions so close in space that their effects overlap. Different types of disturbances 
occurring in the same area can interact synergistically to produce qualitatively different responses 
by the receiving ecological communities. Indirect effects can be produced after a perturbation has 
ceased, or produced some distance away from the site of initial disruption, or result from a complex 
intervening pathway. Incremental and decremental effects can include time and space crowding, as 
well as removal of habitat piece by piece, and result in a "nibbling" away of environmental quality 
and quantity. Threshold developments that stimulate additional activity in a region or projects 
whose environmental effects are delayed (time lags) or are felt over large distances (space lags) can 
produce cumulative effects if their impacts overlap in time or space or are synergistic with those of 
other developments. Examples of not just some, but all of these actions are planned or proposed for 
Galveston Bay and its watershed. 

Information Need 

A comprehensive assessment of the cumulative impacts of all of the present, planned and 
proposed projects that could affect Galveston Bay is critically needed. The assessment should be 
conducted by an independent third party and its design and planning must involve all of the federal 
and state agencies responsible for natural resource protection. 

Ecosystem Interconnections 

Just as phenomena occurring in the riverine and upland ecosystems feeding and surrounding 
Galveston Bay will affect its community structure and productivity, the bay, in turn, exerts significant 
effects on the Gulf of Mexico. The interactions between rivers and the bay, and between bay and gulf 
through the tenuous Bolivar Roads connection, require further study. 

Information Needs 

Many ecosystem-wide and inter-ecosystem questions need to be addressed. How will modifica¬ 
tion of freshwater inflow or saltwater intrusion affect bay circulation, temperature structure, 
productivity, fisheries, ecological communities, and critical habitats? The biota of the lower Trinity 
river habitats is dominated by marine organisms; will construction of a dam near the mouth of the 
river have significant impacts on marine productivity? Will an increase in wastewater discharges to 
the San Jacinto River drainage be functionally equivalent to the concomitant decrease in freshwater 
inflow from the Trinity River? How will bay and continental shelf circulation be affected by 


76 


channelization and open-bay spoil disposal? How do nutrients cycle within the bay and nearshore 
environments? What are the dynamics of toxic contaminants in bay and nearshelf sediments and 
their interaction with, and effects on, the water column and biota? How does bay and offshore 
primary production relate to hypoxia, coastal circulation, development of oceanic fronts and red tide 
phenomena? What are the biological, chemical, physical and geological exchange processes through 
the bay passes and the hydrographic and ecological relationship between the bay and offshore 
environment? How do reproduction and recruitment of fishery species relate to coastal oceano¬ 
graphic processes and man-induced changes in the ecosystem? What are the ecological connections 
between critical bay habitats and important fishery species, such as marshes, seagrass beds, oyster 
reefs, open bay bottom, oysters, shrimp, trout, flounder, redfish, etc. How will sea-level changes 
affect the ecosystem and'its shoreline? What are the ecological impacts of changes in coastal erosion, 
sedimentation and turbidity? 


Conclusions 

It is apparent that a considerable volume of data involving chemical, physical and biological 
parameters has been gathered on Galveston Bay by several state agencies and universities but very 
little of the material has been compiled or analyzed. It is essential that funds and manpower be made 
available to analyze and interpret the existing data to provide the information needed to describe the 
ecological relationships of the bay system. 

The uncertainties are certain to remain until further research resolves the issues. In the meantime, 
since the proposed developments are not time-dependent or constrained, it will be prudent to err on 
the side of conservation. We must avoid ecological brinkmanship, taking care not to step over the 
precipice. We must act to restore and enhance estuarine productivity, lest we be relegated by 
indifference to merely recording its decline. 

References 

1. White, W.A., T.R. Calnan, R.A. Morton, R.S. Kimble, T.G. Littleton, J.H. McGowen, H.S. Nance, 
and K.E. Schmedes, 1985. Submerged Lands of Texas, Galveston-Houston Area. Univ. Texas. 
Bur. Econ. Geol. Spec. Publ., 143pp. Austin, Texas. 

2. Armstrong, N.E., 1982. Responses of Texas estuaries to freshwater inflows, p. 105-120 in 
Estuarine Comparisons (V. Kennedy, ed.), NY: Academic Press. 

3. Gulf Coast Waste Disposal Authority, 1974. A report to the Texas Water Quality Board on 
Galveston Bay Project problem areas. 23pp. 

4. Texas Water Quality Board, 1975. Galveston Bay Project Summary Report. 99pp. 

5. Armstrong, N.E., 1987. The ecology of open-bay bottoms of Texas: a community profile. U.S. Fish 
and Wildlife Service Biol. Rept. 85 (7.12), 104 pp. Washington, D.C. 

6. Kirkpatrick, J. Unpubl. rpt. 

7. Matthews, G.A., National Marine Fisheries Service, pers. comm. 

8. Kendall, J.J., Jr., S.R. Dent, and L.H. Schmidt, 1988. The role of the Texas Water Commission in 
monitoring Galveston Bay. In Galveston Bay in the 20th Century (in press). 

9. Paine, J.G., and R.A. Morton, 1986. Historical shoreline changes in Trinity, Galveston, West and 
East Bays, Texas Gulf Coast. Bur. Econ. Geol. Geol. Circ. 86-3, 58pp. Austin, Texas. 

10. National Research Council, 1986. Ecological Knowledge and Environmental Problem-Solving: 
Concepts and Case Studies. 388pp. Washington, D.C.: National Academy Press. 


77 




































































Management Issues: Galveston Bay 

L.D. McKinney, M. Hightower, B. Smith, D. Beckett and A. Green 1 

LARRY MCKINNEY—Galveston Bay is the seventh largest estuary in the continental United 
States. It is a complex system whose physical characteristics both provide for and confound multiple- 
use management philosophies. 

The complexity of the problem facing resource managers is evident by the contrasting uses to 
which the resource is subjected: 

• The estuary accounts for 20 to 70 percent (depending upon species) of the total fisheries 
production in Texas and one-half of the state's recreational fishing expenditures. 

• More than one-half of the state's wastewater discharge permits are sited within the estuary's 
watershed. 

• Sixty to 70 percent of Texas' oyster fishery is concentrated in the estuary. 

• Galveston Bay is surrounded by the eighth largest metropolitan area in the United States and, 
in the late 1970s and early 1980s, the fastest growing area. 

• Its chief port, Houston, ranks third among United States' ports in total tonnage. 

• The annual direct and induced value of the estuary's natural resources exceeds $994.7 million, 
and, when indirect expenditures are included in the total, annual economic benefits derived 
from the bay's resources are almost $3 billion. 

It is for these reasons, among others, that the fate of Galveston Bay becomes a question of vital 
national importance. 

Galveston Bay shares many problems with other estuaries of a similar stature—chiefly the rapidly 
escalating demands placed upon its resources because of an expanding population and associated 
development. Many issues, such as concerns about water quality, contaminants and habitat loss, are 
issues that must be addressed in practically all urban estuaries. Galveston Bay, however, is unique 
in the combination of two attributes: 

• First, this 600 square miles of shallow, wind-dominated system, with its extensive oyster reefs, 
fringing marshes and open water, is being squeezed between its chief port at the head of the 
bay and the open sea at the other end; 

• And, second, despite the competing uses, Galveston Bay outwardly remains a healthy, 
productive system. 

Its future, however, remains to be determined. Decisions to be made in the next several years may 
well determine its fate, and, for managers, this may be the most critical period in its history. 

The Central Management Question 

The single most important question facing resource managers in this estuary is, with current and 
projected demands upon its resources, can Galveston Bay remain productive? 

Some demands upon the system have yet to be felt. Nonetheless, the potential for an immediate 
and catastrophic impact from instantaneous events such as an oil or chemical spill exists on a daily 


’L.D. McKinney and A. Green represent the Texas Parks and Wildlife Department; M. Hightower, Texas 
Sea Grant Program; C.B. Smith, Texas General Land Office; and D. Beckett, Texas Water Commission. 


79 



basis. Because of the refining and chemical production facilities at the head of the bay, ships must 
transit the productive center of the estuary moving to and from the sea. This is a voyage of more than 
50 miles. As ship size increases because of a deeper and wider channel, or as the number of transits 
by smaller vessels increase, an accident is likely to occur. Should, or perhaps when, this happens it 
is likely to be devastating to the estuaries' resources as low tidal velocities and the configuration of 
the system assures a high potential for damage. 

Other demands upon the bay's resources have already begun to have an effect. The 251 miles of 
deep draft and intracoastal channels that crisscross the bay have come at the cost of almost 40 square 
miles of the bay impaired by channel creation and spoil disposal. This is nearly 6 percent of the bay's 
bottom. If proposed channel projects are completed, some 9 to 10 percent of the bay bottom, or one 
of every 10 acres, will have been dredged or have been impacted by dredge material disposal. 

The estuary accounts for more than 40 percent of Texas shrimp landings, about $64 million in 
annual ex-vessel value. These organisms, along with juveniles of many important finfishes, depend 
on marsh habitat surrounding the bay for both forage and protection from predation. Because of this, 
fisheries production depends in great part on the amount of this habitat that we are able to maintain. 
Subsidence has contributed significantly to marsh loss. Sea level rise has probably played some role 
and may be more significant in the future. The impacts of these types of losses are compounded by 
the lack of expansion room for the creation of new marsh. Typically, as the water level rises existing 
marsh drowns and new marsh evolves further inland, if water depth and tidal flux are favorable, and 
if soil type is appropriate. The problem in Galveston Bay is that much of this productive habitat is 
surrounded by development, both housing and industrial. Bulkheads and filled (elevated) areas will 
not allow for the development of new marsh. Thus, the loss of marsh to open water proceeds without 
compensatory marsh creation. A significant contributing factor to these losses, and perhaps the most 
significant factor because of successful subsidence control efforts, is the wetlands losses due to 
development. Nearly 25 percent of Texas' permitted (Corps of Engineers 404/10 program) coastal 
development occurs within this estuary. For example, in 1987,171 public notices for 404/10 permits 
were issued that requested permission to dredge or fill wetlands. These accounted for 24 percent of 
the annual total. If all requested permits were issued, a total of 219 acres would have been impacted 
(80 percent shallow open water and 20 percent marsh). Some 3.9 million cubic yards of spoil would 
also have been generated. Additionally, 12.7 miles of pipeline, 3.2 miles of bulkhead and 1.6 miles of 
piers would have been constructed. 

Some of the demands on the bay's resources have already necessitated some difficult manage¬ 
ment decisions. In 1981 the Texas legislature banned the commercial fishery for red drum, or redfish 
as it is better known, as well as spotted sea trout in favor of a restricted recreational fishery. Basically, 
there were not enough fish to support both activities. Because recreational fishing is a $443 million 
per year industry in the estuary (based on 1986 dollars), the choice was simple. The decision, 
however, was a hard one because it essentially ended an industry on a statewide basis. The 
commercial ban continues today and through the foreseeable future. Recreational fishermen did not 
escape entirely. There currently is a five-fish-per-person daily limit and a "slot" or size range of 18 
to 30 inches for redfish that can be retained. Above or below that slot, redfish must be released. 
However, there is a 10-fish-per-day limit for spotted seatrout. 

A Corollary Management Question: When? 

Despite these continuing pressures, Galveston Bay has remained a productive system. Conse¬ 
quently, both resource managers and developers have essentially gone their own way, managing 
their own particular piece of the pie. The system seems to have been able to absorb the competing 
demands and has shown remarkable resilience in responding to our use. This may no longer be the 
case as evidenced by the increasingly vocal disagreements between resource and development 
interests. The scale and number of projects proposed for the system, and the early signs of a degrading 
trend in key resources, have brought concerns forward and have made managers realize that 
important decisions are being forced on them now rather than in the future. Two important resource 
issues are illustrative of these concerns — the oyster fishery and freshwater inflows. 

Oyster Fishery 

Texas' chief oyster fishery is concentrated in Galveston Bay (60 to 70 percent). More than 90 


80 


percent of the estuary's oysters are taken from the central area of Galveston Bay proper, a relatively 
small area. In addition, there are numerous oyster leases onto which oysters are transferred from 
polluted waters and allowed to depurate before commercial harvest. Pollution has already closed 51 
percent of the bay's margin because of municipal wastewater discharges, as well as non-point source 
discharges (see Appendix I). Following heavy rainfalls in the immediate watershed the entire bay is 
closed for several days, or longer, depending on the severity of the pollution load. In essence, the bay 
is providing tertiary waste-treatment. If this trend continues unabated, there is some speculation that 
more of the bay may be closed in the future. How much longer can the estuary assimilate these waste 
loads before the productive central oystering reefs are closed because of health hazard? This is a 
question that must be addressed by resource managers, perhaps sooner than we have the answers 
to the problem. 

An additional concern is the impact of future development on this highly concentrated oyster 
fishery. One project, in particular, is the widening and deepening of the Houston Ship Channel 
(GB ANS or HG50 Project). This project could so alter the bay's hydrology that 60 to 80 percent of the 
oyster fishery could be lost. Other equally supported estimates by the constructing agency, the Corps 
of Engineers (COE), minimizes the impacts at less than 10 percent. Because of disagreements about 
the basic validity of the salinity model employed by the COE, no resolution of these widely disparate 
estimates is likely. The argument may be moot, however, as health department officials fear that the 
hydrological changes caused by the project may also redirect polluted water outflow to encompass 
the irreplaceable central reefs. If that were to occur, harvest would cease altogether. Oyster lease areas 
would also be placed off-limits and the transplanting of oysters to "clean" areas would not be 
possible, or, at best, would be greatly restricted. In any event, this fishery is likely to face a severe test 
in the near future. 

A more immediate issue has been one of the oyster fishery's status. Has it been overfished? The 
Texas Parks and Wildlife Department (TPWD) determined that it was and closed the 1988 season. 
Others have made the case that it is not, and that a closed season is not the best means to regulate the 
fishery. Both sides of the issue have cited substantiating data. Nonetheless, the season was closed, 
only to be reopened by the courts on a procedural point in January 1988. Barring flood, drought or 
some other extreme, time will apparently resolve who was correct on this issue. 

Freshwater Inflows 

A second issue, and one of the most critical ones facing resource managers in this and other Texas 
estuaries, is the status of freshwater inflows. The estuary depends on these inflows, primarily from 
rivers, as a source of salinity dilution, nutrients and sediments. A growing population and industrial 
development also needs water. Water that once flowed unimpeded to the estuary is now impounded 
and diverted to meet competing demands. How do we meet both demands? As with other important 
issues we have more questions than answers. 

Existing reservoirs—Conroe, Houston and Livingston—have already affected freshwater in¬ 
flows, both in quality and in timing. Whether their effect has been significant has not been 
demonstrated. Certainly, on an individual basis, and considering their relative distance from the 
estuary and intervening watersheds, reservoir impacts at present do not appear significant. How¬ 
ever, three additional reservoirs are planned, Bedias, Lake Creek and Wallisville. With these 
additions, and in concert with the existing reservoirs, impacts could be cumulatively significant, 
adversely affecting the estuary. Because one of them, Wallisville, is essentially adjacent to Trinity Bay, 
the potential problems are greatly magnified. Not only will water be diverted from the estuary and 
productive habitat (approximately 5,600 acres) lost, but the reservoir will also act as a nutrient and 
sediment sink, denying those vital resources to the estuary. 

The plants and animals of the estuary, especially the important fisheries species, have evolved to 
cycle with and depend upon the seasonal and flooding patterns. How will they react to man's 
alterations of the cycle? Can they adapt? Will different, perhaps less exploitable, species replace 
existing ones? These are yet to be answered questions that are extremely important to resource 
managers. Sabine Lake, just northeast of Galveston Bay, is a notable example of how a fishery has 
been altered and severely degraded by the effects of reservoirs. While a similar fate is not likely in 
Galveston Bay the potential for significant degradation does exist. 


81 


Another important aspect of this issue is the apparent shift of freshwater inflows from east to west. 
The main source of freshwater inflows to Galveston Bay historically has been from the east via the 
Trinity River. As Houston's population has been growing westward so has its associated return 
flows. These return flows are becoming an increasingly significant input of water to the bay system 
and may eventually exceed river flows. What is the implication to the existing salinity regime and, 
perhaps more importantly, existing and projected pollution problems? 

It is these and the other questions that resource managers are being forced to answer. Answers 
that must be provided now, not in the future, because decisions about this estuary's resources are 
being made now, not in the future. 

Current Status of Management 

The governmental organization within the state is such that resource responsibilities are divided 
among several agencies. Additionally, there is no coordinating body or program, like a coastal zone 
management program, other than the state legislature or governor, with overall management 
responsibility for the estuary. 

The following synopsis of agencies and responsibilities is illustrative of state management efforts 
in Galveston Bay. 

Texas Air Control Board 

The Texas Air Control Board (TACB) operates under statutory authority of the Texas Clean Air 
Act. Permits for construction or operation of any facility that has the potential to emit pollutants into 
the atmosphere are required, and are issued by the TACB using guidelines and performance 
standards contained in Board rules. Consultations are held with local pollution control agencies prior 
to permit issuance. All permit applications undergo a review process to evaluate facility plans and 
specifications prior to issuance. Operation permits must be obtained within 60 days after a facility 
begins operation unless an extension is granted by the Board. The TACB also does engineering 
studies for Point Source Discharge (PSD) permits that are issued by the U.S. Environmental 
Protection Agency. 

Texas Historical Commission 

The Texas Historical Commission (THC) is responsible for preserving and protecting the state's 
historical and archaeological resources, and operates under authority of the National Historic 
Preservation Act of 1966. Federally sponsored projects, such as reservoir construction and surface 
mining activities, are reviewed and permits are required by the THC as necessary to protect state 
resources. The Texas Antiquities Committee (TAC), a division of the THC, deals with projects not 
receiving federal funds and operates under statutory authority of the Texas Antiquities Code. 

The TAC regulatory process plays a key role in protecting archaeological and cultural resources 
such as sunken ships, buried treasures, art works and prehistoric habitation sites in the coastal area 
(see Appendix I). The Committee issues eight types of permits covering virtually every aspect of 
historical and archaeological investigation, and may also require pre-project archaeological surveys 
to determine if sensitive resources will be affected by construction, dredging or filling activities 
related to private or federal projects in submerged areas. Rules and regulations established by the 
Committee outline detailed specifications for investigators and require comprehensive reporting of 
survey results. 

General Land Office and School Land Board 

The Texas General Land Office and School Land Board manage surface and mineral resources of 
state-owned lands that have been dedicated to the state's public school fund. This includes 
approximately 860,000 acres of uplands and 4 million acres of submerged land in rivers, bays and the 
Gulf of Mexico. 

The three-member School Land Board, which is chaired by the Commissioner of the General Land 
Office, issues grants of interest on state-owned upland property for various purposes including oil 
and gas production, hard mineral production, hunting, timber harvest, and grazing. Permits are also 
issued for activities on submerged lands, including exploration and development of hydrocarbon 
reserves, dredging of channels, and construction of various structures such as piers, docks, wharves 


82 


and marinas. Easements are also granted for roads, transmission lines and pipeline rights-of-way on 
state lands. The General Land Office also has statutory authority to grant leases for public recreation, 
preserves and refuges, and scientific research activities on state-owned lands. 

The application process for each type of permit involves an environmental review procedure and 
a determination of the highest and best use of state resources. This review process is coordinated with 
other state and federal regulatory agencies, and includes the development of contractual conditions 
that will protect natural resources on state lands, or provide for mitigation where environmental 
damage is unavoidable. 

Texas Department of Health 

The Texas Department of Health (TDH) administers the Molluscan Shellfish Sanitation Program 
and the Municipal Solid Waste Program. 

The TDH's Division of Shellfish Sanitation Control is responsible for classifying coastal waters 
according to their acceptability for harvesting molluscan shellfish. As a result of shoreline sanitary 
surveys, portions of estuaries may be closed because of the actual or potential presence of contami¬ 
nants. These areas are classified as "polluted" by the TDH and harvest of shellfish from them is not 
allowed. The department also regulates molluscan shellfish processing plants. Construction or 
modification of these plants require departmental certification. 

The TDH issues permits for municipal solid waste disposal on the basis of performance standards 
contained in its rules. State law allows counties to exercise permitting authority over municipal solid 
waste disposal if they conform to Department requirements. As of this date, however, no counties 
has assumed permitting authority over municipal solid waste facilities. Where municipal and 
industrial wastes become mixed as part of normal collection processes, the TDH has jurisdiction over 
that mixed waste. An exception to this jurisdiction is Class 1 industrial waste, which must be disposed 
of in a facility approved by the Texas Water Commission. The Texas Water Commission also has 
jurisdiction over industrial solid waste. 

Texas Parks and Wildlife Department 

The Texas Parks and Wildlife Department (TPWD) manages fish and wildlife resources of the 
state by the licensing of hunting and sport fishing activities, and manages numerous programs to 
protect or manage fisheries resources and wetlands. The Department also plays an active role in other 
state and federal permit activities by reviewing and commenting on permits issued by other state and 
federal agencies. 

The TPWD has significant legislative responsibility for wetland protection, is the state agency 
designated to comment on federal 404 permits, and is the state's coordinating agency for federal 
water development projects and permits. 

The TPWD also regulates removal and/or disturbance of sand, shell or marl in state-owned 
waters, operates and manages an extensive system of state parks and state wildlife refuges, and 
administers the Texas Natural Heritage Program created in 1983 to collect and make available data 
on sensitive and unique natural flora, fauna and habitats within the state. 

Texas Railroad Commission 

The Texas Railroad Commission (TRRC) was originally created to regulate railroads, but now 
exercises permitting authority in many areas, including surface transportation, surface mining and 
restoration, and oil and gas production and transport. 

Activities of the TRRC, which are of particular importance in submerged areas, include the 
regulation of brine discharges from oil and gas operations, enforcement of well casing and cementing 
requirements, regulation of well abandonment procedures, and governance of oil and gas activity 
reporting procedures. These activities are designed to minimize pollution in submerged areas. 

Texas Water Development Board 

The Texas Water Development Board (TWDB) is responsible for preparation of a State Water Plan 
and administers various funds that support reservoir construction and flood control projects. This 
plan evaluates downstream impacts of watershed alterations, impoundments and other modifica¬ 
tions to Texas rivers and streams. State-funded reservoir construction and flood control projects 


83 


include studies that are prepared by the TWDB in cooperation with the Texas Parks and Wildlife 
Department to evaluate estuarine inflows and changes to bay circulation dynamics. 

Texas Water Commission 

The Texas Water Commission (TWC) is charged with maintaining and protecting the quality of 
all waters of the state, allocating state waters, and with regulating the disposal of industrial solid 
waste pursuant to the Solid Waste Disposal Act. 

The TWC also regulates activities that may alter the course of rivers or streams in Texas, and is, 
therefore, involved in reviewing activities that involve clearing, channelization or draining of 
wetland areas. 

In addition, the TWC reviews applications and issues permits for domestic and industrial sewage 
disposal systems. Provisions are contained in permits to ensure that discharge from the facilities will 
not degrade the state's water resources. The agency levies fines for permit violations or unauthorized 
discharges. 

National Pollutant Discharge Elimination System (NPDES) permits issued by the U.S. Environ¬ 
mental Protection Agency to regulate disposal of waste into submerged areas must first be certified 
by the TWC. The TWC also issues permits for Industrial Solid Waste Disposal, and requires 
registration of all waste disposal sites. TWC certification is also required as part of the U.S. Army 
Corps of Engineers' permit process on all dredge and fill projects in jurisdictional wetlands. 

TWC shares responsibility for regulating liquid and solid waste with the Texas Department of 
Health. 

State Department of Highways and Public Transportation 

The State Department of Highways and Public Transportation(SDHPT) has been designated as 
the local sponsor for the Gulf Intracoastal Waterway (GIWW), and is charged with providing 
disposal sites for dredged materials generated by periodic waterway maintenance and construction 
activities. The state legislature allocates funds to the SDHPT for procurement of disposal sites. The 
SDHPT also chairs the Gulf Intracoastal Advisory Committee, which is composed of representatives 
of key state agencies, industry representatives and concerned citizens groups who provide input and 
recommendations regarding disposal site procurement. 

The primary role of the SDHPT is road construction and planning, administering funds for 
improvements to state highways and Texas roads that are not part of the state highway system, and 
administering mass transit and public transportation programs. Although the SDHPT is not a 
permitting agency from the natural resource standpoint, it plays a key role in the overall management 
and planning of coastal projects, due to its role as local sponsor of the GIWW, and the need to ensure 
adequate public evacuation routes during times of natural disasters such as hurricanes. The SDHPT 
also maintains and operates many bridges and ferries across the state. 

Office of the Attorney General 

The Texas Attorney General's office is the enforcement arm of the state government. Although it 
is not a regulatory agency per se, its involvement in coastal preservation and protection on behalf of 
other state agencies during litigation make it an important participant in the coastal regulation 
process. 

The Office takes an active role in protection of the public right to beach access and brings suit on 
behalf of the various state agencies as needed to enforce compliance with state laws. 

Management Successes 

Because of the number of state and federal agencies, among whom regulation and management 
activities are divided, the development of policy and management goals have tended toward specific 
agency responsibilities, rather than toward a more comprehensive management approach. This has 
hampered our ability not only to provide important data to decision-makers, because the information 
may simply not have been collected, but also we may have failed to ask the right questions. Certainly, 
basic questions have remained unanswered. 

Nonetheless, there have been management successes. Resource managers have not been sitting 
on their hands, either statewide or regionally. In many cases noticeable improvements in resource 


84 


protection and enhancement have occurred. The commitment to move forward and focus available 
resources on specific problems has increased dramatically in the last several years. 

The Houston Ship Channel 

Most notable among the efforts to quantify and mitigate the effects of pollutants on the major 
source of freshwater to Galveston Bay has been the effort to clean up the Houston Ship Channel. The 
Ship Channel was characterized as one of the 10 most polluted water bodies in the United States in 
the 1960s. Hundreds of industrial and domestic plants discharged an estimated 175,000 pounds per 
day of oxygen-demanding wastes to the waterway in 1970. Dissolved oxygen levels in the Channel 
Turning Basin averaged 0.25 mg/L in 1969. The monitoring station at the entrance to Galveston Bay, 
some 30 miles downstream of the Turning Basin, maintained an average of 5 mg/L dissolved oxygen. 

Since that time, the Texas Water Commission and its predecessor water quality agencies have 
instituted and implemented a number of programs to clean up the channel. Not only have the 
oxygen-demanding materials been addressed, but also the many toxic pollutants and metals that 
previously went unregulated. Much more stringent wastewater permits are now in effect and are 
being enforced, permittees' self-reporting requirements have been expanded, intensive surveys and 
sediment studies have been conducted, and non-point source evaluations have been undertaken. 

By 1982, point source originated biochemical oxygen-demanding loads had decreased by two- 
thirds to 62,000 pounds per day. According to monitoring station data, the water from the Houston 
Ship Channel carried approximately 8.5 mg/L dissolved oxygen to Galveston Bay, supporting an 
improved estuary, rookery and fishery. The water in the Turning Basin has eight times as much 
oxygen (2.0 mg/L) and the many harmful pollutants are now largely controlled. The best efforts of 
scientists, engineers and planners and the investment of millions of dollars in pollution treatment 
equipment have brought the Houston Ship Channel, tributary to Galveston Bay, back to life. 

Protection and Enhancement of Colonial Waterbirds 

While open bay spoil disposal has been the source of much controversy, there has been some 
benefit derived from those areas where spoil has created emergent islands. Many thousands of 
colonial waterbirds have taken advantage of these generally isolated areas to use as rookeries. The 
Texas General Land Office, Corps of Engineers and conservation groups, especially the Audubon 
Society, have cooperated to protect and enhance a number of critical areas. 

The Gulf Intracoastal Waterway (GIWW) 

This important waterway bisects the upper Galveston Bay and all of Trinity Bay from the 
remainder of the estuary. As with other navigation channels, maintenance dredging entails the 
disposal of spoil material. Disposal sites that do not affect shallow bay bottom or associated wetlands 
are becoming more difficult to find. Many of the existing upland sites are nearing capacity. In 
response to this problem the state's GIWW sponsor, the Texas Department of Public Highways and 
Transportation, formed the Gulf Intracoastal Waterway Advisory Committee (GIWAC) to address 
and prioritize problems on a coastwide basis. 

GIWAC, comprised of state and federal resource agencies, has had some success in addressing 
this complex problem. Experimental disposal methods, spoil impact studies and site studies for new 
disposal areas have resulted from GIWAC efforts. Several member agencies, such as TPWD and the 
U.S. Fish and Wildlife Service (USFWS), have been especially active in seeking disposal alternatives. 
In addition, the 70th Texas Legislature appropriated $1 million to purchase or lease spoil disposal 
sites. GIWAC has identified the upper coast for priority consideration. All of these activities have 
important implications for Galveston Bay because the current means of spoil disposal there, as in 
several other Texas bays (open bay as opposed to upland or offshore sites), is a primary cause of 
habitat loss and a source of concern about resuspension of contaminants. 

Freshwater Inflows 

The Texas Legislature has also mandated studies, directed by TPWD and the Texas Water 
Development Board (TWDB), to assess the freshwater inflow needs of Texas' seven major estuarine 
systems. The studies are due to be completed in the next two years and should provide basic 
information on hydrology and productivity as related to freshwater inflows. The legislature has also 


85 


provided the means to implement study results in the form of legislation and the formation of 
advisory councils, one for each of the major estuaries, to develop management priority and policy. 
Once again, Galveston Bay is an important focus of these studies. These studies represent a significant 
commitment in both effort and fiscal resources to provide some important answers, not only for 
Galveston Bay, but for all seven of the state's major estuaries. 

New Opportunities 

In addition to the programs and activities just discussed, three recent actions could have 
significant impact on management of this estuaiy. It is also interesting to note that these actions 
originated from federal and state officials and a group of concerned citizens. It is these three entities 
and the actions they have taken that are key to the development of any progressive management 
within the estuary. 

Comprehensive Study of Cumulative Impacts 

Because of the number and scope of development projects, especially federal navigation and 
reservoir projects in and around the estuary, state and federal resource agencies have become 
increasingly alarmed about the future of Galveston Bay. The number of reservoirs above the estuaiy 
could be doubled, from three to six. Changes because of reservoirs, either by diversions, alterations 
of historic seasonal flows, or in the quality or release point of return flows could become a significant 
concern. The bay bottom impacted by navigation channels and spoil disposal could be increased by 
more than 80 percent. Potentially, one in every 10 acres of bay bottom will have been dredged or have 
disposed spoils if current planning is fulfilled. 

As a result of growing concern, the state's major resource agencies — TPWD, TWC and GLO — 
have called for a comprehensive study of the cumulative impacts of all of these activities on the 
estuary. This request was supported by federal resource agencies — USFWS and National Marine 
Fisheries Service (NMFS) — and by conservation groups, such as the Gulf Coast Conservation 
Association (GCCA), the Sierra Club, Audubon Society and Sportsmen's Clubs of Texas (SCOT), and 
by resource organizations, such as the Texas Shrimp Association (TSA), Gulf Coast Fisheries Council 
and others. Perhaps for the first time, these many and diverse entities have joined in a common 
purpose: A concern for the future of Galveston Bay. 

Galveston Bay — An Estuary of National Significance 

Passage of the Water Quality Act of 1987 amended, and extended, the Federal Water Pollution 
Control Act of 1972 and its 1977 amendments, known as the Clean Water Act. The Water Quality Act 
formally established the National Estuary Program. A part of the Act also names Galveston Bay, 
along with several others, as estuaries of national significance. Texas' governor has already made the 
initial request to establish the required management conference. The lead agency, Texas Water 
Commission, with the support of TPWD, GLO and other resource agencies and academic institu¬ 
tions, is preparing the necessary documentation to enable the state to take full advantage of the 
program. This action has received widespread support from other state and federal agencies and 
conservation groups. 

Galveston Bay Foundation 

A group of prominent individuals from diverse backgrounds met in the Fall of 1987 to form an 
organization centered on the state's single most valuable natural resource — Galveston Bay. The 
Galveston Bay Foundation has quickly become a focal point for citizens concerned about the fate of 
this estuary. In addition, the Foundation is funding studies to answer questions about competing 
uses of the bay's resources. It is this type of citizen concern and active participation that is key to 
providing management and policy direction to those governmental agencies responsible for the 
estuary's resources. 


Summary 

The opportunity exists in the Galveston Bay system to manage its resources for multiple uses, yet 
not allow the system to degrade and eventually be forced into a costly recovery program as has been 


86 


necessary in Chesapeake Bay. Galveston Bay remains a relatively healthy and productive estuary, 
but the early warning signs of future problems are clear. Now is the time to establish the policies and 
goals to guide the bay's future. In Galveston Bay we certainly have a case where "an ounce of 
prevention is worth a pound of cure." 

The issues, problems and conflicts presented in this paper, and throughout this symposium, are 
symptomatic of the cumulative strain being placed on the estuary's resources. The fragility of our 
opportunity to manage this system successfully is reflected in the short time we have to make the 
right decisions and, where needed, to generate the necessary information. Our options will lessen 
with time and decisions will have to be made, either by us or, through inactivity, they will be made 
for us. 

As resource managers, we are in a race to not only find answers, but to ask the right questions. 
To do this we must tap the resources of our scientific community and work with one another as 
managers. In this estuary we have a resource of national importance. It is deserving of our best efforts 
to maintain its health, because we cannot afford to lose one of this nation's most valuable resources 
— Galveston Bay. 


87 
































































Summary 

Terry E. Whitledge and Sammy M. Ray 

TERRY WHITLEDGE—The Galveston Bay estuary has an ecosystem that has endured both the 
use and abuse of a highly populated urban and industrial complex and agricultural production while 
maintaining fisheries harvests and supporting other water-related sporting activities. There have 
been measurable declines in many important components in the Galveston Bay estuary and we fear 
that more detrimental changes will emerge in the future. The Galveston Bay complex (Trinity, 
Galveston, East and West Bays) is still producing a large harvest of shellfish and finfish for 
commercial and sports fishermen and it provides a valuable habitat for many other important species 
such as waterfowl and shore birds. But many of the people who know and appreciate Galveston Bay 
for what it was in the past and for what it is now are concerned about what it will he in the future. 
Management decisions that are being made now will determine the Galveston Bay of the future. In 
making these decisions, too much information cannot be provided but at this time there are many 
questions and even fewer answers about what should be done to protect or improve the health of 
Galveston Bay. Hopefully, concerned citizens, bay users, state agencies, university scientists and 
federal agencies can formulate a coalition that can study the problems and implement solutions and 
preserve the future of Galveston Bay as a national resource. 

General Characteristics 

All of the estuaries that are designated asbeing nationally significant share some common general 
properties that contribute to their importance. Some of the other 196 estuaries in NOAA's national 
estuary analysis have one or more but only a few, including Galveston Bay, will have a combination 
of several or all of the following properties: 

1. Large Surrounding Human Population — The Galveston Bay watershed extends more than 300 
miles and includes Dallas-Fort Worth as well as the Houston metropolitan areas for a combined 
population of about 6.8 million people. The city of Houston and related suburbs (population 2.8 
million) occupy an extensive part of the shoreline of the San Jacinto River and upper Galveston 
Bay. 

2. Area of High Growth and Development — The growth of the Houston and other surrounding 
areas of Galveston Bay is among the highest in the nation. This includes both permanent 
residences such as housing developments and tourist-related service industries. 

3. Industrial Importance — The four-county area of Galveston Bay contains more than 50 percent 
of the total U.S. production of petrochemicals and refines more than 30 percent of the petroleum 
products. The port of Houston has the third largest tonnage of all U.S. ports and there are more 
than 4,000 vessels that transit the 50-mile long Houston ship channel each year. 

4. Toxic and Eutrophic Discharges — The Galveston Bay system directly receives more than half 
of the permitted discharges in the State of Texas. These discharges emanate from a wide range 
of chemical industries and municipal wastewater treatment plants. The discharged water can 
contain significant concentrations of organic chemicals, petroleum byproducts, heavy metals, 
pathogens, nutrients, organic matter and waste heat. The Houston ship channel, in particular, 
has been insulted with many of these substances in the past but there has been some improve¬ 
ments in the past five to ten years. 


89 


5. Large Fisheries Harvest — The popularity of redfish and spotted sea trout effected a decline in 
these fish species so commercial harvests were banned in 1981. Sport fishermen still catch an 
estimated 3.2 million pounds of these organisms while commercial catches primarily rely on 
flounder, sand trout and sheephead. Oyster harvests fluctuate greatly from year to year 
depending on freshwater inflow and diseases, but the average output has remained a dominant 
product of Galveston Bay. Shrimp harvest both for human consumption and fish bait has 
continued to be a major product of Galveston Bay, which produces about 30 percent of the total 
Texas catch. Waterfowl hunting for geese and ducks is an important industry for the agricultural 
regions around Trinity and East Bays. 

6. Changing Habitats — The loss of habitat may be the most profound alteration occurring in 
Galveston Bay because that is a direct change in the ecosystem. The saltwater marshes have 
diminished in size as a result of subsidence of land, water level rises, diversion of freshwater, 
holding of freshwater by dams and landfills and bulkheading for developments. Seagrass bed 
losses as high as 90 percent also mean a loss of habitat for larval and juvenile forms of important 
fishery species. Another important habitat change concerns the deep channels that have been 
dug for commercial boat traffic that allow high salinity water to enter and transit across the 
shallow bay. The dredge spoils from channelization produced emergent islands and dikes in 
Galveston Bay, which has both good and bad aspects. Finally, freshwater diversion has changed 
the salinity gradient in the bay system, which has a marked effect on key organisms such as 
oysters that need freshwater inflow to avoid marine predators and diseases. The diversion of 
freshwater also alters the input locations to a more urban area where biological populations are 
less able to cope with a multitude of insults. 

Special Characteristics 

Galveston Bay and other Texas estuaries have some special characteristics that contribute to their 

vulnerability and are partially responsible for our current lack of understanding of some of the 

important processes. These prominent features include: 

1. Shallow Depths—The mean depth of Galveston Bay is 2.1 meters (6.5 feet). The main navigation 
channel is 50 miles long with a depth of 45 feet and a width of 100 feet. The undisturbed bay 
bottoms are very shallow with numerous reef areas. 

2. High Water Temperature — The waters of Galveston Bay reach temperatures in the vicinity of 
30 °C in the summer months. 

3. High Wind Speeds—The weather patterns produce high winds at all times of the year while the 
predominate direction changes from the southeast in the summer to the north in the winter. 

4. Large Evaporation/Precipitation Ratio — The high summer temperatures and wind speeds 
combine to produce a large evaporation/precipitation ratio. In south Texas, this process makes 
Laguna Madre hypersaline. As the precipitation increases from west to east in Texas, Galveston 
Bay has nearly equal precipitation and evaporation. This factor greatly influences the salinity 
distribution of Galveston Bay. 

5. Small Freshwater Inflow — Although Galveston Bay is located near the wettest region of the 
state, freshwater is a valuable resource and there is competition for that resource. Overall, about 
75 percent of freshwater is used for agricultural purposes and 20 percent is allocated for 
industrial and domestic uses. This leaves about 5 percent for the bays and estuaries. More dams 
and other freshwater uses are being planned so the flow of freshwater needed to maintain the 
estuaries' ecosystem is in jeopardy. 

6. Small Physical Circulation — The influence of tides on currents is relatively small in Texas bays. 
The mean tidal fluctuation is about 2 feet inside Galveston Bay while maximum range is about 
2.6 feet. The wind becomes very important in both the horizontal movement and vertical mixing 
of bay waters. Normal tidal predictions without wind factors are not very accurate when 
compared to actual water heights in Galveston Bay. 

7. Large Biological Production — In good years, as much as 10 to 15 percent of oyster landings in 


90 


the United States comes from Galveston Bay. Galveston Bay also contributes 31 percent of the 
total finfish and shellfish catch in the combined total of inshore-offshore fisheries of Texas. 

Research Needs 

The following research needs of Galveston Bay, developed by the Galveston Bay Seminar group, 
are derived from management questions and a lack of research analyses and data. The research needs 
are not ranked in order of importance but are grouped into general and specific categories that have 
been emphasized by the EPA guidelines on priority research topics in estuaries. The categories 
discussed are general research, toxicants, pathogens, eutrophication, habitat loss and living re¬ 
sources. 

General Research Needs 

1. Understand Water Circulation Patterns — Almost all studies of important processes in 
Galveston Bay would require knowledge of water movements as shown in time dependent two- 
or three-dimensional models. At the present time no current meter moorings have been placed 
in Galveston Bay; only vertical profiles using hand-held current meters have been taken over a 
few hours or days. Current meter moorings are necessary for testing the validity of time 
dependent models and they should be deployed in several diagnostic locations in the bay system. 

2. Assess and Analyze Existing Data — Several state agencies, departments and boards collect data 
in Galveston Bay. These data sets should be coalesced and analyzed for trends and rates to the 
extent that is practical. The spatial and temporal resolution of the data may not be adequate for 
definitive results but trends may be extracted. Universities and other research organizations may 
be able to contribute additional data. 

3. Quantify Cumulative Impacts — Multiple stresses can be placing additional impacts on the 
ecosystem that are not considered in tightly focused studies. For instance, upper Galveston Bay 
may be stressed at one location by dredging, eutrophication and permitted discharge of 
industrial waste. An inclusive study should be developed for each situation that would assess 
the total impact of the multiple stresses. 

4. Delineate Ecosystem Interconnections — The river, bay and Gulf waters provide a continuum 
of habitats from freshwater to saltwater that is necessary for estuarine organisms. If the ecology 
of any of these waters is changed, the resources in the others will probably be affected. Most of 
the organisms in Galveston Bay utilize the habitat in more than one of these areas. 

Toxicants 

1. Concentration of Toxins — The concentration of toxic material in water, sediment and biota is 
not well known in Galveston Bay. Some values are known in the Houston ship channel, but a 
comprehensive survey has not been undertaken for the whole bay complex. 

2. Temporal Changes — The concentration of toxicants in sediments where large values are 
observed has not been sampled adequately to discern temporal changes. 

3. Effects on Nursery Areas — The specific effect of toxicants on nursery areas such as saltwater 
marshes or seagrass beds has not been adequately studied. 

4. Mobilization in Dredge Spoil — Dredge spoil can either be isolated or utilized but there is a 
controversy over its disposal. The primary question relates to the extent of mobilization of 
contaminants that occur during dredging operations. 

5. Biological Uptake — We may know that sediments are contaminated with toxicants but we 
cannot presently estimate transfer coefficients of toxic materials from sediments into organisms. 
Until we can estimate the rate of accumulation of toxicants in animals we will not be able to 
predict their effect on the biota accurately. 

6. Sublethal Effects — Toxic materials may have significant effects in addition to killing organisms. 
Most of the endocrinology, reproduction and behavioral effects occur at lower effective concen¬ 
trations of toxic materials and those effects are more subtle than death but could be just as 
significant. 


91 


7. Synergistic Effects — The synergistic effects of several toxicants, such as heavy metals, synthetic 
organic compounds and petroleum, can increase an effect to equal more than the sum of the 
insults. This effect may produce results that are much worse than predicted. 

Pathogens 

1. Current Trends — Shellfish beds and swimming areas that are closed should be assessed for 
current trends. Given the present discharge and runoff loading, an assessment should be made 
to foresee any changes in these areas. 

2. Loading — An assessment should be made of the relative contribution of domestic, industrial 
and agricultural discharges to pathogen loading. 

3. Non-Point Sources — The role of urban runoff needs to be compared to other non-point sources. 

4. Accidental Discharges — An assessment of the contribution of accidental or uncontrolled 
(overflow) municipal discharges should be determined. 

Eutrophication 

1. Linear or Nonlinear Effects — The knowledge of effects of a reduction in nutrient loading is not 
well understood. At the present time it is known that reductions in loading decreases nutrient 
concentrations in upper Galveston Bay and other estuaries but it is not known whether the effects 
are linear or nonlinear. The addition may produce a significant lag time due to long mean 
residents times. 

2. In Situ Regeneration — The in situ regeneration of nutrients is highly significant in shallow 
estuaries so the relative importance of this process compared to inputs into the bay ecosystem 
needs to be assessed. 

3. Point and Non-Point Sources — The relative amounts of point and non-point sources of nutrient 
loading need to be determined. Attempts to locate estimated amounts of fertilizer application to 
agricultural lands have been unsuccessful due to lack of adequate records. 

4. Point Source Impacts — The mini-environment around point sources receive larger insults than 
far-field regions. More knowledge about the severe effects near discharge points is needed. 

5. Relationship to Other Processes—Nutrient loading of bay waters may have profound effects on 
natural processes such as denitrification, nitrification, nitrogen fixation and decomposition. The 
interaction of these processes in eutrophic environments is neither well known nor quantified. 

6. Nutrient-Light Interaction — No comprehensive knowledge of nutrient versus light limitation 
of microalgae primary production in Galveston Bay is available. There are large turbidity factors 
from freshwater inflow and wind mixing that can be uncoupled from nutrient inputs. Other 
Texas bays apparently have distinct regions of light-limitation and nutrient limitation. 

7. Relationship of Hypoxia to Discharges — The hypoxic events that occur in the Galveston Bay 
estuary are apparently related to overflows of waste treatment facilities. It is not known whether 
a significant background of organic loading already exists to enhance a minor discharge to cause 
a large impact. 

8. Effects of Hypoxia and Anoxia — The overall effects of hypoxia and anoxia on the biota are not 
known. The possible effects range from minor mortalities to complete losses of year classes or 
spawning populations. The areas of impact may be small but the loss of entire populations or 
organisms may take years to restore. 

Habitat Losses 

1. Future Trends or Losses — The significant losses of Galveston Bay wetlands in the recent past 
have been caused by subsidence from petroleum and water extraction and a mean sea level rise. 
The future losses by these continued processes are not known but a prediction is needed to guide 
effective management strategies. 

2. Creation of Wetlands — As wetlands disappear from Galveston Bay, new wetlands could be 
created by planned spoil disposal and other techniques. The rate of creation of new wetlands that 
matches the decline of submerged wetlands may be difficult to accomplish because of the conflict 


92 


with its current use by our populations. There is a related question of whether man-made 
marshes would function like natural marshes. 

3. Habitat Substitution — If it is not possible to create new wetlands, alternate habitats like artificial 
reefs could be constructed. It is not known to what extent such a substitution can replace a 
wetland. If we do create new reef areas there is an additional concern about altering the ratio of 
shallow/deep water in the bays. 

4. Submerged Aquatic Vegetation Losses — The cause of disappearance of 90 percent of seagrass 
beds in Galveston Bay is not known. Several of the possible factors range from eutrophication, 
turbidity from freshwater inflow or proximity to shipping lanes such as the Intracoastal 
Waterway to herbicides from agricultural runoff. Seagrasses were previously located in several 
areas of Galveston Bay so the cause may be distributed over the entire estuary. 

5. Relationship to Biota — There are significant populations of waterfowl and larval fishes that 
utilize seagrasses for food or shelter. It is not known whether the decline in seagrass will also 
affect a further decline in these associated organisms. 

Living Resources 

1. Finfishes — The commercial fishing for redfish and spotted sea trout were closed as the 
population declined. The relationship of the combined effects of contaminants, loss of habitat 
and overfishing are not known. 

2. Shellfish — There are several construction proposals that will change the timing and quantity of 
freshwater inflow. Dams level out the water flow with smaller peak flows and higher low flows 
so the prospects of future oyster and shrimp production are uncertain. Predators and disease 
decimate oyster populations if high salinity values occur, while white shrimp populations 
cannot thrive without freshwater flow. A more detailed cause/effect response needs to be shown 
for these impacts. 

3. Resource Recovery — The living resources have declined or are threatened by toxicants, 
pathogens, eutrophication, habitat losses and harvesting. Many of these stresses can be reduced 
with good management strategies but it is uncertain how quickly the biological populations can 
rebound. 


93 

















































Keynote Address 

The Honorable Lloyd Bentsen 1 
United States Senate 


The Galveston Estuary—the seventh largest in the United States—has been a magnet for 
commerce and progress throughout the centuries. 

Named in honor of Governor Galvez of Louisiana, it became a base of operations for the pirate 
Jean Lafitte, who called it Campeche and set out to raid Spanish commerce. When one of Lafitte's 
captains took it upon himself to capture and sink a U.S. merchant ship in 1820, the pirates were 
quickly ordered off the island by the American government. 

The moment their ships cleared the harbor, American settlers began to arrive. When Texans 
fought the historic battle of San Jacinto, Galveston was the temporary capital. During the Civil War, 
this city was the chief Confederate supply port on the Gulf of Mexico, and the scene of much fighting. 

We are here because we understand that the battle of Galveston Bay has taken on a new form. 
Today, in the 1980s, we are fighting for the survival of this estuary. 

In war and in peace, during pirate raids and in periods of peaceful commerce, through hurricanes 
and through the centuries, the Galveston Estuary has been a source of life—and livelihood—for an 
entire region. 

After centuries of growth and change, the delicate ecology of this estuary—and many others in 
the United States—hangs in the balance. Current trends, if left unchecked, could turn Galveston Bay 
into another Lake Erie. 

When we debated the Clean Water Act in the Senate Environment and Public Works Committee, 
I made it a special point to see that Galveston Bay was included in the select list of priority estuaries 
of national significance. 

Some of you here today played key roles in helping to get that designation and I look forward to 
working with you, through the Galveston Bay Foundation, to find honest answers to the competing 
demands of development and conservation. As some of you know, I am an ex-officio member of the 
Galveston Bay Foundation. It is dedicated to finding honest answers to the competing demands of 
development and conservation in and around the bay. Members of the Foundation may be divided 
on specific issues; they may be traditional adversaries on development questions, but they are united 
in a common determination to save this bay. 

A comprehensive, broadly supported management plan to preserve and enhance water quality 
can save the estuary—and that is why we are here today. 

This conference is the coming together of a wide variety of experts who have devoted a great deal 
of time and talent to the problems of managing Galveston Bay. The federal government is ready to 
help; Governor Clements' office is involved; state agencies such as Parks and Wildlife, the Water 
Commission and the General Land Office are committed to a cooperative, comprehensive program 
for the bay. 

Our job is to see that Galveston Bay is healthy, fertile, rich and lovingly nurtured. 

And that will be a difficult task. There are not many places I know of where you have a very fragile, 
delicate 600-square-mile ecosystem that provides a major source of foodfish, shellfish and game fish; 


The Honorable Mr. Bentsen is Senior Senator from the State of Texas. 


95 



that is home to waterfowl and wildlife; that provides beaches, sport and commercial fishing, and 
recreational facilities for millions of Texas; and is surrounded by more than 3 million people living 
in four counties. 

There is agricultural fertilizer washing into the estuary. It is traversed by hundreds of miles of ship 
channels. It provides access to America's third largest port. And it is virtually surrounded by 
petroleum, chemical and other manufacturing facilities critical to the economic well-being of our 
state and national economy. 

As Chairman of the Senate Finance Committee, I can tell you that budget and fiscal realities make 
it clear that Galveston Bay will not be saved in Washington. The federal government can help. It can 
provide the impetus for conferences such as this. NOAA can play a role. But the hard work and the 
sacrifice and the tough choices will have to be made by Texans. 

And that is really the way it should be. We are the ones who must accept responsibility for the 
destiny of a body of water that has been the source of so much life and commerce for so many 
centuries. 

Protecting the Galveston Estuary will be a tough job, but it has to be done. Fortunately, we have 
the people to do it. We have Texans, working together to preserve one of our state's most important 
assets. 

I believe the Galveston Estuary has a future as bright as its past. 


96 


Appendix I 
Supporting Figures 


The following illustrations of Trinity, Galveston, East and West Bays of the Galveston Bay 
complex are included to accompany each segment of this proceedings. 


97 


OIL AND GAS DEVELOPMENT 


THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY, EAST AND 
WEST BAYS 






PAST AND PRESENT OIL AND 
GAS WELL SITES 

AREAS CURRENTLY LEASED FOR 
MINERAL PRODUCTION 

MAJOR PIPELINES 









SEISMIC EXPLORATION ACTIVITY 


THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY, EAST AND 
WEST BAYS 



































FEDERAL NAVIGATION CHANNELS 
AND DISPOSAL AREAS 



THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY, EAST AND 
WEST BAYS 


SCALE: 1”=1.9 Miles 


DESIGNATED FEDERAL PROJECT 
SPOIL AREAS 

PROPOSED FEDERAL PROJECT 
SPOIL AREAS 

EXISTING CHANNELS 
PROPOSED CHANNELS 


100 








SENSITIVE CULTURAL RESOURCES 


THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY, EAST AND 
WEST BAYS 




101 








SENSITIVE BIOLOGICAL RESOURCES 


THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY, EAST AND 
WEST BAYS 



PRIME FISH, CRAB AND SHRIMP 
HARVEST AREAS 

IMPORTANT ROOKERY SITES FOR 
MIGRATORY WATERBIRDS 


102 







OYSTER FISHERIES RESOURCES 
OF GALVESTON BAY 


THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY, EAST AND 
WEST BAYS 





a 

NATURAL OYSTER REEFS 


PRIVATE OYSTER REEFS 

•\VL 

POLLUTED ZONE CLOSED TO 

OYSTER HARVEST 









GALVESTON BAY SYSTEM WATERSHED 



CANADIAN 


OKLAHOMA 


SULPHUR 


MEXICO 


LOUISIANA 


COLORADO 


SABINE 


- TRIMITY 

TRINITY* 

SAN JACINTO 


SAW JACINTO 


SAN JACINTO 


COLORADO 

LAVACA 


v LAVACA 
LAVACA- 
GUAOALUPC 


GUADALUPE 


SAN ANTONIO 


<» V SAN ANTONIO 


Nueces- 

RIO GRANOC 


104 











































FRESH WATER FLOWS AND 
POINT SOURCE DISCHARGES 


SAN JACINTO RIVER FLOW 
1.4 MILLION AC/FT/YR 

W 


TRINITY RIVER FLOW 
5.0 MILLION AC/FT/YR 


THE GALVESTON BAY 
SYSTEM INCLUDING 
TRINITY. EAST AND 
WEST BAYS 



LOCAL DRAINAGES 
2.5 MILLION AC/FT/YR 


105 











Appendix II 
Steering Committee 
and 

Resource Personnel 


107 


Steering Committee 


Galveston Bay Description 
Physical Components 

Gary Powell, Section Co-chair 
EG. Wermund, Jr., Section Co-chair 
Robert Morton 

Biological Components 

R. Douglas Slack, Section Chair 
Edward Klima 
Larry McKinney 
Sammy Ray 
Peter Sheridan 

Human Uses, Production and 
Economic Values 

Robert Ditton, Section Chair 
Robert Harbaugh 
Dewayne Hollin 
Joe Kolb 
H.T. Kornegay 

Estuary Management 

Mike Hightower, Section Chair 

Dan Beckett 

Sally Davenport 

Albert Green 

Larry McKinney 

C. Bruce Smith 


Catherine Albrecht 
Texas Water Commission 
4301 Center Street 
Deer Park, Texas 77536 

David V. Aldrich 
Department of Marine Biology 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Charles Allen 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

John Anderson 
Rice University 
P.O. Box 1892 
Houston, Texas 77251 

Bob Armstrong 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 


Issues and Information Needs 

Thomas J. Bright, Section Co-chair 

Robert McFarlane, Section Co-chair 

Glenn Aumann 

Brian Cain 

Sally Davenport 

Albert Green 

Robert Harbaugh 

James Kendall 

Edward Klima 

Joe Kolb 

Donald Moore 

Allan Mueller 

Gary Powell 

Russell Putt 

Robert Reid 

E.G. Wermund 

Terry Whitledge 


Neal Armstrong 

Department of Civil Engineering 
The University of Texas at Austin 
University Station, Box X 
Austin, Texas 78713 

Connie R. Arnold 

The University of Texas at Austin 

Marine Science Institute 

P.O. Box 1267 

Port Aransas, Texas 78373 

Vic Arnold 

Department of Management 
College of Business Administration 
The University of Texas at Austin 
Austin, Texas 78713 

Glenn Aumann 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 


108 


Richard Baldauf 

Houston Museum of Natural Science 
1 Hermann Circle Drive 
Houston, Texas 77030 

Dan Beckett 

Texas Water Commission 
Capitol Station 
P.O. Box 13087 
Austin, Texas 78711-3087 

Richard (Lynn) Benefield 
Texas Parki and Wildlife Department 
Seabrook Marine Laboratory 
Seabrook, Texas 77586 

A.R. Benton Jr. 

Remote Sensing Center 
Texas A&M University 
College Station, Texas 77843 

James Blackburn, Chairman 
Galveston Bay Foundation 
3003 W. Alabama, Suite 205 
Houston, Texas 77098 

Charles Branton 
9300 Elm Grove Circle 
Austin, Texas 78721 

Randy Bright 

Gulf Coast Conservation Association 
4801 Woodway, Suite 220W 
Houston, Texas 77058 

Thomas Bright, Director 
Sea Grant College Program 
Texas A&M University 
College Station, Texas 77843-4115 

David A. Brock 

Texas Water Development Board 
P.O. Box 13231 
Austin, Texas 78711 

James Brooks 

Department of Oceanography 
Texas A&M University 
College Station, Texas 77843 

Richard Browning 
Trinity River Authority 
Energy Resources Program 
P.O. Box 60 

Arlington, Texas 76010 
C.E. Bryan 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

Edward J. Buskey 

The University of Texas at Austin 

Marine Science Institute 

P.O. Box 1267 

Port Aransas, Texas 78373 


Brian W. Cain 

Division of Ecological Services 
U.S. Fish and Wildlife Service 
17629 El Camino Real, Suite 211 
Houston, Texas 77058 

Glenda Callaway 
Ekistics Corporation 
3400 Westheimer No. 18E 
Houston, Texas 77098 

Thomas R. Calnan 
Bureau of Economic Geology 
The University of Texas at Austin 
University Statio, Box X 
Austin, Texas 78713 

Gene Campbell 
Charter Boats 
14 Quailwood 
Baytown, Texas 77521 

Alfonso Castillo 
Texas Department of Health 
Shellfish Sanitation Control 
P.O. Box 218 
LaMarque, Texas 77568 

Henry Chafetz 
Department of Geosciences 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

George Chamberlain 

Texas A&M Research and Extension Center 

Route 2, Box 589 

Corpus Christi, Texas 78410 

Col. Gordon M. Clarke 

District Engineer, Galveston District 

Department of the Army 

U.S. Corps of Engineers 

P.O. Box 1229 

Galveston, Texas 77553 

Jerry Clarke 

Chief, Coastal Fisheries 

Texas Parks and Wildlife Department 

4200 Smith School Road 

Austin, Texas 78744 

Dennis Clifford 
Environmental Engineering 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

Rez Darnell 

Department of Oceanography 
Texas A&M University 
College Station, Texas 77843 

Sally Davenport 

Land Management Program 

General Land Office 

1700 N. Congress Ave., Suite 620 

Austin, Texas 78701 


109 


Louis Delhome 
Houston Boating Association 
2600 Southwest Freeway, Suite 305 
Houston, Texas 77098 

T. Dillon 

Waterways Experiment Station 
P.O. Box 631 

Vicksburg, Mississippi 39180-0631 
Robert B. Ditton 

Department of Wildlife and Fisheries Sciences 
Texas A&M University 
College Station, Texas 77843 

Bob Egan 

Hollywood Marine, Inc. 

P.O. Box 1343 
Houston, Texas 77251 

Ernest Estes 

Department of Marine Science 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Linda Farrow 
Capitol Station 
P.O. Box 12428 
Austin, Texas 78711 

Daniel Fesenmaier 

Department of Recreation and Parks 

Texas A&M University 

College Station, Texas 77843 

Robert Finley 

Bureau of Economic Geology 
The University of Texas at Austin 
University Station, Box X 
Austin, Texas 78713 

Frank M. Fisher 
Department of Biology 
Rice University 
P.O. Box 1892 
Houston, Texas 77251 

Neil Frank 
Chief Meteorologist 
KHOU-TV11 
P.O. Box 11 
Houston, Texas 77001 

John P. Fraser 
Shell Oil Company 
P.O. Box 4320 
Houston, Texas 77210 

Charles Ganze 
Gulf Coast Waste Disposal 
910 Bay Area 
Houston, Texas 77058 

Bob Grabrasch 

U. S. Coast Guard 
300 East 8th Street 
Austin, Texas 78701 


Albert Green 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

Jim Green 

Harris County Hood Control 
9900 Northwest Freeway, Suite 220 
Houston, Texas 77092 

John M. Green 

Gulf of Mexico Fisheries Management Council 
P.O. Box 2611 
Beaumont, Texas 77704 

Dr. Wade Griffin 

Department of Agricultural Economics 
Texas A&M University 
College Station, Texas 77843 

Guy Grossman 
Texas Railroad Commission 
P.O. Drawer 12967 
Austin, Texas 78711-2967 

Herb Grubb 

Texas Water Development Board 

Planning Division 

P.O. Box 13231 

Austin, Texas 78711-3231 

George J. Guillen 

Texas Parks and Wildlife Department 
Seabrook Marine Laboratory 
Seabrook, Texas 77586 

H. Dale Hall 

U.S. Fish and Wildlife Service 
17629 El Camino Real, Suite 211 
Houston, Texas 77058 

Roy W. Hann, Jr. 

Department of Civil Engineering 
Texas A&M University 
College Station, Texas 77843 

R. Harbaugh 

Chief, Environmental Research Branch 
U.S. Army Corps of Engineers 
444 Barracuda 
Galveston, Texas 77553 

Ed Hargett 

Federal Emergency Management 
Region 6 
800 N. Loop 288 
Denton, Texas 76201 

Steve Hamed 
National Weather Service 
Rt. 6 Box 1048 
Alvin, Texas 77511 

Donald E. Harper, Jr. 

Department of Marine Biology 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 


110 


John Herbich 

Department of Civil Engineering 
Texas A&M University 
College Station, Texas 77843 

Mike Hightower, Deputy Director 
Sea Grant College Program 
Texas A&M University 
College Station, Texas 77843-4115 

Dewayne Hollin 
Sea Grant College Program 
Texas A&M University 
College Station, Texas 77843-4115 

Tom Hults 

Texas Oyster Association 
Seabrook Seafood Co. 

P.O. Box 1776 
Kemah, Texas 77565 

Edward Ibert 

Galveston County Health Department 
1207 Oak 

LaMarque, Texas 77568 

David Jenkins 
Trinity River Authority 
P.O. Box 65 
Stowell, Texas 77661 

Robert S. Jones 

The University of Texas at Austin 
Marine Science Institute 
P.O. Box 1267 
Port Aransas, Texas 78373 

Ronald A. Kaiser 

Department of Recreation and Parks 
Texas A&M University 
College Station, Texas 77843 

Tom Kearns 

Texas Water Commission 
15531 Kuykendahl, Suite 350 
Houston, Texas 77090 

Frank Kelly 

Department of Civil Engineering 
Texas A&M University, 

College Station, Texas 77843 

James Kendall 
Texas Water Commission 
4301 Center Street 
Deer Park, Texas 77536 

Lauriston King 

Office of University Research Services 
Texas A&M University 
College Station, Texas 77843 

Steve Kleinberg 
Department of Sociology 
Rice University 
P.O. Box 1892 
Houston, Texas 77251 


Edward F. Klima, Director 
National Marine Fisheries Service 
4700 Avenue U 
Galveston, Texas 77553 

Joe W. Kolb 

Texas Water Commission 
15531 Kuykendahl, Suite 350 
Houston, Texas 77090 

H. Thomas Komegay 
Director of Engineering 
Port of Houston Authority 
P.O. Box 2562 
Houston, Texas 77001 

Andre Landry 

Department of Marine Biology 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Brent Latts 

Texas Department of Health 
P.O. Box 218 
LaMarque, Texas 77568 

Berdon Lawrence 
Hollywood Marine 
P.O. Box 1343 
Houston, Texas 77251 

James Lawrence 
Department of Geosciences 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

Richard Leach 
Port of Houston Authority 
P.O. Box 2562 
Houston, Texas 77001 

Fred LeBlanc 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

Bill Longley 

Texas General Land Office 
1700 N. Congress 
Austin, Texas 78701 

John Lunz 

Waterways Experiment Station 
P.O. Box 631 

Vicksburg, Mississippi 39180-0631 

Bob Mason 
U.S. Coast Guard 
Marine Safety Office 
601 Rosenberg 
Galveston, Texas 77550 

Tommy Mason 
Texas Water Commission 
Capitol Station 
P.O. Box 13087 
Austin, Texas 78711-3087 


111 


Gary C. Matlock 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

Jack Matson 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

Geoffrey Matthews 
National Marine Fisheries Service 
4700 Avenue U 
Galveston, Texas 77550 

James McCloy 

Acting Vice President for Academic Affairs 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

John McEachran 

Department of Wildlife and Fisheries Sciences 
Texas A&M University 
College Station, Texas 77843 

Robert W. McFarlane 
McFarlane & Associates 
9503 Sharpview 
Houston, Texas 77036 

Larry McKinney 

Environmental Assessment 

Texas Parks and Wildlife Department 

4200 Smith School Road 

Austin, Texas 78744 

Carlos Mendoza 
US. Fish and Wildlife Service 
17629 El Camino Real, Suite 211 
Houston, Texas 77058 

William J. Merrell, Jr., President 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Theodore Metcalf 

Department of Virology and Epidemiology 
Baylor College of Medicine 
Texas Medical Center 
Houston, Texas 77030 

Russell Miget 
Marine Fisheries Specialist 
Sea Grant College Program 
P.O. Box 158 

Port Aransas, Texas 78373 

Brian Middled itch 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

Thomas J. Minello 
National Marine Fisheries Service 
4700 Avenue U 
Galveston, Texas 77551 


Paul Montagna 

The University of Texas at Austin 
Marine Science Institute 
P.O. Box 1267 
Port Aransas, Texas 78373 

Donald Moore 

Southeast Fisheries Center 

Galveston Laboratory 

National Marine Fisheries Service 

4700 Avenue U 

Galveston, Texas 77550 

Richard Morrison 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

Robert A. Morton 
Bureau of Economic Geology 
The University of Texas at Austin 
University Station, Box X 
Austin, Texas 78713 

Bruce Moulton 
Texas Water Commission 
4301 Center Street 
Deer Park, Texas 77536 

Allan J. Mueller 
U.S. Fish and Wildlife Service 
17629 El Camino Real, Suite 211 
Houston, Texas 77058 

Capt. Munson 
U.S. Coast Guard 
P.O. Box 446 

Galena Park, Texas 77586 
Kris Murthy 

Texas Water Commission 
15531 Kuykendahl, Suite 350 
Houston, Texas 77090 

Robert Nailon 

Texas Marine Advisory Service 
P.O. Box 699 
Anahuac, Texas 77514 

William H. Neill 

Department of Wildlife and Fisheries Sciences 
Texas A&M University 
College Station, Texas 77843 

David W. Neleigh 

US. Environmental Protection Agency 
1445 Ross Avenue, Suite 1200 
Dallas, Texas 75202-2733 

E. Taisoo Park 

Department of Marine Biology 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Patrick L. Parker 

The University of Texas at Austin 
Marine Science Institute 
P.O. Box 1267 
Port Aransas, Texas 78373 


112 


Larry Peabody 
National Weather Service 
830 N.E. Loop 410, Suite 300 
San Antonio, Texas 78209 

Eric Powell 

Department of Oceanography 
Texas A&M University 
College Station, Texas 77843 

Gary Powell 

Texas Water Development Board 
P.O. Box 13231 Capitol Station 
Austin, Texas 78711 

B.J. Presley 

Department of Oceanography 
Texas A&M University 
College Station, Texas 77843 

Russell Putt 

U.S. Environmental Protection Agency 
1445 Ross Avenue 
Dallas, Texas 75202 

Ralph Rayburn 
Texas Shrimp Association 
403 Vaughn Building 
Austin, Texas 78701 

Sammy M. Ray 

Department of Marine Biology 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Robert Reid 

Department of Oceanography 
Texas A&M University 
College Station, Texas 77843 

Thomas Rennie 

Environmental Research Branch 
U.S. Army Corps of Engineers 
P.O. Box 1229 
Galveston, Texas 77553 

Susan Rieff 

Texas Parks and Wildlife Department 
4200 Smith School Road 
Austin, Texas 78744 

Leland Roberts 

Resource Protection Branch 

Texas Parks and Wildlife Department 

4200 Smith School Road 

Austin, Texas 78744 

B.C. Robinson 
Rice University 
P.O. Box 1892 
Houston, Texas 77251 

George Rochen 

U.S. Army Corps of Engineers 

P.O. Box 1229 

Galveston, Texas 77553 


Hubert L. Roger 
Houston Sportsmen's Club 
P.O. Box 70612 
Houston, Texas 77270 

Mel C. Russell 

Texas Marine Advisory Service 
5115 Highway 3 
Dickinson, Texas 77539 

Harold Scarlett 
The Houston Post 
P.O. Box 4747 
Houston, Texas 77210-4747 

Ken Schaudt 
Marathon Oil Company 
P.O. Box 3128 
Houston, Texas 77253 

David Schmidly, Head 

Department of Wildlife and Fisheries Sciences 
Texas A&M University 
College Station, Texas 77843 

A.R. Schwartz 
10 South Shore Drive 
Galveston, Texas 77551 

Eddie Seidensticker 
Soil Conservation Service 
P.O. Box 819 
Anahuac, Texas 77514 

Peter Sheridan 

National Marine Fisheries Service 
4700 Avenue U 
Galveston, Texas 77550 

R. Douglas Slack 

Department of Wildlife and Fisheries Sciences 
Texas A&M University 
College Station, Texas 77843 

C.J. Smith 

Public Works-Houston 
P.O. Box 1562 
Houston, Texas 77251 

C. Bruce Smith 
Land Management Program 
Texas General Land Office 
1700 North Congress, Suite 620 
Austin, Texas 78701 

Gerald Speitel 

Department of Environmental Engineering 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

C.L. Standley 

PISCES, Galveston Bay Chapter 
Rt. 3, Box 348 
Dickinson, Texas 77539 

Sharron Stewart 

Texas Environmental Coalition 

P.O. Box 701 

Lake Jackson, Texas 77566 


113 


John R. Stoll 

Department of Agricultural Economics 
Texas A&M University 
College Station, Texas 77843 

James M. Symons 

Department of Environmental Engineering 
University of Houston 
4800 Calhoun 
Houston, Texas 77004 

Peter Thomas 

The University of Texas at Austin 
Marine Science Institute 
P.O. Box 1267 
Port Aransas, Texas 78373 

Richard Thompson, Director 
Shellfish Sanitation Control 
Texas Department of Health 
1100 West 40th 
Austin, Texas 78756 

Bob Vickery 

Environmental Protection Agency 
Renaissance Tower 
1201 Elm Street 
Dallas, Texas 75270 

Donn Ward 

Texas Marine Advisory Service 
Texas A&M University 
College Station, Texas 77843 

George Ward 

Espey, Huston & Associates, Inc. 

P.O. Box 519 
Austin, Texas 78767 

Jim Webb 

Department of Marine Biology 
Texas A&M University at Galveston 
P.O. Box 1675 
Galveston, Texas 77553 

Gerard M. Wellington 
Marine Sciences Program 
University of Houston 
4700 Avenue U, Building 305 
Galveston, Texas 77550 

E.G. Wermund, Jr. 

Bureau of Economic Geology 
The University of Texas at Austin 
University Station, Box X 
Austin, Texas 78713 

Fred Werner 

U.S. Fish and Wildlife Service 
17629 El Camino Real, Suite 211 
Houston, Texas 77058 

William A. White 
Bureau of Economic Geology 
The University of Texas at Austin 
University Station, Box X 
Austin, Texas 78713 


Terry Whitledge 

The University of Texas at Austin 
Marine Science Institute 
P.O. Box 1267 
Port Aransas, Texas 78373 

Meg Wilson, Coordinator 

Center for Technology Development and 

Transfer 

College of Engineering 

The University of Texas at Austin 

Austin, Texas 78712-1080 

Harry Young 

Oil Spill Training School 

Texas Engineering Experiment Station 

P.O. Box 1675 

Galveston, Texas 77553 

Richard Yuill 
Department of Biology 
Rice University 
P.O. Box 1892 
Houston, Texas 77251 

Roger Zimmerman 
National Marine Fisheries Service 
4700 Avenue U 
Galveston, Texas 77550 


114 


























































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